London in the late Victorian era sports a music hall theatre where Chinese magician Li H'sen Chang is getting applause from a crowd. He is entertaining them with his dummy which he calls Mr. Sin. After the act, the cigar smoking London Palace Theatre manager, Mr. Henry Gordon Jago, praises Chang's act. Backstage, a cab driver cockney man named Buller, arrives to blame Chang for the disappearance of his wife Emma who was here the night before. Chang brings the man up to his room with Sin and a younger Chinese servant boy. Jago thinks Chang is courteous -- he would have given the man a punt up the posterior.

In Chang's dressing room, Buller tells Chang that his wife Emma was acting "queer" ever since Chang levitated her last week and that he knows she was here last night. Chang tells him a saying -- that a man that goes too quickly may step in bear trap. Buller leaves to go fetch the police. Chang looks at Mr. Sin and the dummy nods his head in return.

People walk near a river and despite the fog as ships make their noise along with nearby trains this night. The TARDIS appears on a small cobbled street near the Thames. Leela feels silly in her period piece clothes and hat but the Doctor tells her the skins she always wears would scare the horses. The Doctor is dressed like Sherlock Holmes with cap to match. Leela thinks a horn of a ship is the same sound of a swamp creature when it attacked. Leela thinks the Doctor, not answering her and making her wear this outfit, is trying to annoy her. He claims he is trying to teach her and wants to bring her to the theatre. He finds a poster of Chang but was hoping for Little Teich.

At the Palace Theatre, Casey, the Irish door man, tells Jago that he saw "it" more fully this time. He has seen and heard strange things before this night but this time it resembled a skull coming at him out of the dark cellars. Jago does not want rumors of ghosts and hauntings to ruin his business and asks Casey if he's been drinking. When Casey responds in the negative, Jago offers him a swig from a hip fisk, "Well, it's time you started!"

Buller, walking down a narrow street, sees something jump off a barrel. It is Mr. Sin, the dummy walking at him with a drawn knife.

Leela comments this is a huge village as she and the Doctor walk, not far from Sin and Buller. The Doctor explains the tribe here are called Cockneys. They hear Buller scream, which Leela notes is "the sound of death." The Doctor tells her to stay there and runs ahead. He finds four or five Chinese men carrying Buller's body off. The Doctor asks if he can help and they attack him. He throws them off of him and flips one over his head. Another gets on his back and starts hitting his head. Leela arrives and tosses this one off the Doctor, hitting him against a wall, and fights others. The Doctor is down and there are too many Chinese surrounding Leela, backing her into the dead end of the alleyway, several different weapons drawn. Leela gasps but a police whistle scares all but one Chinese attacker away. This one menaces her some more but then tries to run off. The Doctor from below, trips him and this gives Leela the chance to detain the man. The Doctor gets up and moves to chase the others but they are long gone. He finds blood on the sewer man hole cover and thinks they have gone below. The police arrive and the Doctor finds Leela menacing them. The Doctor greets the constable who tells him that when he arrived, the Chinese man was being strangled by this savage girl using his own pigtail! The police want Leela, the Doctor, and their prisoner to come to the station.

At the theatre, Chang levitates a girl from on her back to up in the air. He claims the girl is in deep hypnosis but Sin sarcastically comments she is just asleep and keeps trying to reveal Chang's secret trick for levitating her. The servant boy moves chairs away from the girl and the audience sees she is floating in thin air. Chang stops Sin's heckling and pulls out a crooked sword, Sin making as if he is afraid of Chang. Chang uses it to show the girl has nothing under or above her. Jago, watching from backstage, notices blood dripping from Sin's left arm down his sleeve.

At the police station, the sergeant questions the Doctor and Leela, mostly about them. He asks about where they live -- their fixed abode. The Doctor tells him they have an abode but it is not fixed. The Doctor moves off and says something such as the sergeant is an idiot. The sergeant asks what he said and the Doctor tells him nothing complimentary. The Doctor is here to give evidence about kidnapping, robbery, and possibly a murder. The sergeant gives him a hard time about no evidence of a murder. The Doctor frustrates and asks Leela to tell him. Leela explains the man was stabbed through the heart and she knows the different sounds of death as a warrior of the Sevateem tribe. She wants the prisoner to made to talk by putting him to the torture. The police sergeant blocks her from the Chinese attacker, who is sitting at a table. The Doctor moves to the prisoner, smiling and telling the Sergeant he speaks Mandarin, Cantonese, and all the dialects. A police whistle from the Thames area is blown.

Another floater -- a body -- has been seen at the river by an old woman. The police arrive and see a body floating in the water. A fish hook is found and used to bring the body to shore. The lady comments that what is left of the body would make a horse sick.

Chang arrives at the police station to help with the prisoner -- perhaps translate and figure out what has happened. Chang is surprised Leela caught the man. The Doctor thinks he knows Chang who comments they all look alike to the white men. The Doctor ignores that and thinks, perhaps he met him in China but the Doctor comments, "No, that can't be it. I haven't been in China for over 400 years." Chang sits at the table with the prisoner and asks for paper and pencil from the sergeant. When the sergeant is moving off, Chang slips a small pill from his ring and the Chinese prisoner takes it and puts it in his mouth. The Doctor suddenly returns to Chang, recalling where he saw him -- on the poster -- and ask him for a trick. The attacker suddenly gasps and falls over the table. The Doctor laughs, thinking it was a magic trick, but the attacker is really dead. The Doctor checks the hand of the dead man and sees a tattoo mark on the man's arm -- a scorpion mark. The Doctor realizes this is the mark of the Tong of the Black Scorpion, a dangerous criminal organization and that the man died of concentrated scorpion venom. Chang remarks that the Doctor seems remarkably well informed and makes his leave, not without telling Leela he's sure they will meet again. The Doctor orders the sergeant to begin procedures to do a post mortem on the man -- the Doctor is here to help. He orders the sergeant to do as he says and start getting an autopsy in motion.

Chang's coach rides the streets past a building with a poster about the murders of 8 victims.

At the theatre, Jago and Casey are finishing closing for the night. Casey wonders if Jolly Jack -- Jack the Ripper -- is back. Jago thinks it is just newsmen gossip for Grub Street. Casey is sent to turn off the gallery lights. Jago sneaks into Chang's dressing room and looks at Mr. Sin, who is in a basket. He sees the blood on the thing's arm. Footstep sounds herald the arrival of... Casey, who scared Jago accidentally. Jago thought the dummy was some kind of midget but found it was not. Casey thinks Jago has changed his mind about looking in the cellar but Jago tells him that Henry Gordon Jago has determination and rises to the challenge, just before ushering Casey on ahead of him, "After you..."

Leela and the Doctor walk the streets, heading for mortuary. The Doctor explains to Leela that the cult of the Tong followed the "god" Weng-Chiang who they waited for to come rule the world. Chiang was thought to blow poison fumes from his mouth and white light from his eyes which could kill. He tells Leela it is not magic but superstitious mumbo-jumbo.

They arrive at Professor Litefoot's mortuary near the river. The Doctor is told by the guard outside not to go in. The Doctor tells him not to worry, gently tapping his cane on the guard. He goes in, followed by Leela. Inside, the Doctor takes Litefoot's flask of green liquid for him. The white haired old man asks who the devil the Doctor is. The Doctor tells him he has come to help and claims an animal may have made the marks on the body Litefoot is currently examining -- Buller's body. The two deduce a rodent could make those teeth marks but not that size and that the teeth marks were made after death. Death was caused by a knife to the heart and the man had a licence to drive a cab. The body also had hairs that were three inches long. The Doctor recognizes the hairs as that of a rat and recalls another fact about Weng-Chiang -- he was supposed to be the "god" of abundance, growth. The Doctor wants to check on something outside and goes, followed by Leela.

The Doctor tells Leela to stay at the mortuary. He makes his way down a street. A Chinese man comes out of a doorway and follows, holding an axe. The man throws it and it misses the Doctor and hits near his head. The Doctor turns and moves to the man, "Were you trying to attract my attention?" The man just stares and gasps, then falls. A large Janus thorn is in his back. Leela stands behind where the man once stood. The Doctor starts to berate Leela, telling her he ordered her not to carry Janus Thorns. Leela counters by reminding the absent minded Doctor he was trying to kill him. So, he tells her she'd better come along.

The Doctor and Leela run for the ladder. The Doctor buys them some time by hurling a flare at the thing and sparking a small blast at it. They make their way up to the street, away from the monster rat which the Doctor deduces is ten feet long and is guarding something even worse.

At the Palace Theatre, Casey and Jago look in the cellar, Casey talking of demented souls in hell. They see a large ugly face -- a totem pole left behind by Six Gun Sadie and her Wild West troop. Jago mentions the river Fleet runs under the foundations so perhaps the sounds Casey heard were from the ships. Jago finds a monogrammed lady's glove with the initials EB.

At the police station, Sergeant Kyle tells the Doctor the police do not have a plan of the sewers but Litefoot left a message to meet him at the mortuary. Another Chinese body was found. The sergeant asks them about whether or not they had any knowledge of it. Leela starts to tell him, "Of course, we do, I was there right behind..." The Doctor yells at her to come on. They go out.

At the theatre, Jago teases Casey, telling him to go and not be mistaken for one of the girls who vanishes. Jago locks up and finds Chang near the stage door. As his eyes glow brilliantly, Chang hypnotizes Jago to forget that Mr. Buller came here at all. After this, Chang descends to the cellar and down a concealed entrance to a lower chamber lab where he kneels to Weng-Chiang -- a tall figure dressed in black with a long cloak, wearing a full face mask like a helmet and a hat over that. Chiang tells him they must find the Time Cabinet -- he is dying and without it, he will get worse. The victims' life sources are used to keep him alive until they can find the Time Cabinet. Chang explains about a stranger who has arrived, a doctor, tall with pale face and wide eyes and hair that curls like a lamb. Chiang does not think Chang's opium addicted scum can deal with an enemy of such intelligence. Chang will deal with him the Doctor personally

At the mortuary, Litefoot feels beaten which surprises the Doctor, who claims to have dabbled a bit in mortuary science. A zoologist has looked at the body and felt rats could have made the bites. Another piece of information comes from the angle of the wound -- a midget killed Buller. Litefoot doesn't think they should be talking about these things in front of the "fairer sex" and "a lady of refinement". Leela asks the Doctor if he means her... A police officer arrives and reports Buller's first name was Joseph and he lived at 14 Fish Lane. His mother in law, Nellie Gusset, claimed his things. Buller married Emma 6 months ago. The officer did find out that Buller went to the Palace that night to find Emma. After the officer leaves, Litefoot invites the Doctor and Leela to share a dinner with him.

As they ride in the coach, Litefoot lights a pipe which Leela watches astonished, asking why he puts a fire in his mouth. The Doctor tells him that where Leela comes from there is no tobacco. Litefoot thinks that healthy but dull. Litefoot admits he doesn't understand the Chinese and he was brought up in China. His father was a Brigadier General in the Punitive Expedition in 1860 and stayed on as a Palace attaché. Litefoot's father died there and there were fireworks at the funeral which the Doctor tells him were to ward off evil spirits. The Doctor makes the coach stop and leaves, telling them he will meet them later. After he goes, Litefoot wonders how -- he didn't give the Doctor the address. Leela tells him the address -- the Doctor, as she, heard Litefoot give the address to the coach driver -- 4 Round Skill Gardens.

Before Jago can fully lock up, the Doctor enters and introduces himself to the man, who thinks the Doctor is part of an act. Jago tells him auditions are on Saturday at 10AM. The Doctor takes a pot and covers it with a cover and opens it -- a dove is inside now. He tells Jago his performance also can include his skill at performing dramatic recitations, singing, tap dancing, and play the Trumpet Voluntary in a bowl of live goldfish. Jago tells him not to bother coming back on Saturday. The Doctor also claims to be a master hypnotist and takes out a watch. Despite Jago thinking his iron will and Rock of Gibraltar mind can withstand it, the Doctor hypnotizes Jago into telling what he was told by Chang to forget. The Doctor makes Jago remember all of what happened, including Buller being here. They go down to the cellar, the Doctor telling Jago he is helping the police. Jago doesn't think Chang could be involved with the missing women until he realizes the missing girl Emma's initials are EB just like on the glove he found. He shows the glove to the Doctor.

In the night, on the streets, Chang's hansom cab clatters on. Inside it, Weng-Chiang tells Chang (who holds Mr. Sin on his lap) he must have the Time Cabinet. Tomorrow, Chang will get Weng-Chiang two new girls to replenish his strength.

At the palace theatre, the Doctor and Jago go to the cellar where the Doctor finds a money spider -- bigger than the Doctor's hand -- a genetic disruption. Jago doesn't want the Doctor to kill it; the Doctor had no intention of killing it. The Doctor starts throwing things aside from the floor where a trap door might be. As the Doctor moves to another area which is also to the river Fleet below, the ghost skull appears. Jago, who called Casey a good fellow but a table with round corners, now asks Casey to forgive him... and passes out. The Doctor kicks some stuff Jago dropped and starts pulling Jago to safety.

At Litefoot's house, Leela and Litefoot find a meal in the dining room left for them by Litefoot's maid -- Mrs. Hudson. Leela picks up a large piece of meat and eats with her hands. Litefoot stokes up the fire. Leela asks him if something is wrong. Amazed at her eating habits, he tells her no. He asks if she would like a knife and fork. She takes a large knife and cuts the meat. Litefoot puts his plate down and starts eating the same way Leela is eating. The two smile at each other.

In Chang's cab, Weng-Chiang's orb glows, meaning the Time Cabinet is in a house nearby -- near Litefoot's house.

Leela drinks right out of a large bowl. Litefoot tells her to wipe her hands on the napkin instead of the table cloth. She does and also wipes her mouth with her arm! Litefoot looks out the window's curtains in the hopes of spotting the Doctor but he sees a Chinese man ducking into the shrubberies. He takes a pistol from out of a desk drawer, tells Leela to wait inside, and goes out.

At the Palace Theatre, the Doctor sits next to Jago against a wall. Jago asks that Casey forgive him. The Doctor tells him the ghost was a hologram, just light caused by a laser beam and not something for him to worry about. From the top of his cane, the Doctor pulls out a small tube and gives a drink of something to Jago, something which will calm him down. They see a shadow. The Doctor follows it to the stage. The Doctor chases it up through the back of the stage, playing cat and mouse with Weng-Chiang, among the curtains. Weng goes up to the rafters. The Doctor starts up a ladder but Weng tosses a horse head prop down at the Doctor, who falls off the ladder onto a chair beneath. Chiang climbs up higher and then downward. The Doctor follows upward and misses Weng-Chiang climb to a lower level. He does see the tall figure swing to another area but not to where he ran off to. Weng-Chiang pushes the Doctor from behind. The Doctor falls through the wood rail and yells, holding onto the curtain which rips, dropping the Doctor slowly. Weng slides down another, more vertical rope, and hides behind curtains. He is able to hit Jago from behind when the man comes to see if he can help the Doctor. The Doctor falls but the ripped curtain and rope beneath help save his fall from being fatal. He tells a recovering Jago, "Cheer rup, Jago, cheer up." The Doctor tells Jago they will tackle this strange enemy together, "...you and I." First the Doctor tells him he will think and then have supper.

Litefoot finds nothing outside his house and goes back inside.

Leela throws the large knife into Sin's neck, barely slowing him down. Chang is over Litefoot in the hallway and hears the Doctor whistling a song. Chang exits with Litefoot's revolver and hides in the bushes, waiting to shoot the Doctor. The Doctor walks right into his range and as he is about to pull the trigger, Leela jumps out of Sin's reach onto a chair and up from that onto the table. She runs the length of it and dives through the glass window, the crashing sound of which makes the Doctor duck... right out of the bullet Chang has just fired. The Doctor runs to the wall of the house where Leela is. Chang calls Sin off and then carries him out of Litefoot's house. The Doctor goes to the back of the house, telling Leela to wait at the wall. He jumps up onto a barrel off the backsteps and up into another window. Leela sees a coach driving off with Chang and Sin inside. She runs to the back of it and clings to a luggage shelf. The Doctor comes out of the front of the house and sees her doing this. He calls to her to come back but it is too late.

The Doctor gets an icepack for Litefoot's head. They wonder what the Chinese wanted to steal -- perhaps a vase from Peking, Litefoot suggests. The Doctor sees the cabinet which Litefoot calls a Chinese puzzle box which he had checked for a secret spring, to no avail. He has not been able to open it. It was a gift from Emperor Tungchi to Litefoot's family and is made of lacquered bronze. The Doctor recognizes it as the Time Cabinet and it is made of fused molecules. The parallax synchrone and a trionic lattice are aspects of the Time Cabinet itself, the twisted lunacy of a scientific dark age. The technology is not from this time. The Doctor wonders about Weng-Chiang and worries, "I do hope that girl, Leela, isn't in danger."

Leela is watching Chang in the cellars under the palace theatre. Chang bangs on a trap door which opens to him. Leela hears the Chinese man talking to someone else -- Weng-Chiang who is using a meat cleaver to cut up large amounts of meat and threaten Chang is he fails again. He hits the gong to summon the giant rats and tosses the meat into a barred area -- which has some space beneath it. A covering door has to be opened; this door covers the bars totally. A giant rat eats the meat.

At Litefoot's house, Litefoot finds it is morning and the Doctor hasn't slept. Knowing what the poor girl victims are being used for, the Doctor has made a map of the sewers on Litefoot's table cloth which Litefoot wants to throw out into his laundry basket when they are finished with it -- Litefoot doesn't want Mrs. Hudson to see it as a map! The Doctor is given an elephant gun by Litefoot when he asks for something with that type of firepower. The Doctor also asks to hire out a small boat.

Leela followed Chang to the apartment of a young blond girl who gets out of a coach that morning to go to her apartment. Chang stops her and is called Ching Ching by the girl. Leela is hidden behind a wall of a garden. Chang uses his glowing eyes to hypnotize the girl whom he takes back to his room at the Palace Theatre. Leela follows but has to hide when he comes back down the steps. He hears three cleaning ladies laughing and goes to check them out. Leela sneaks up to the room and sees "the spell of the Shaman" on the blond girl. Chang quietly takes the youngest cleaning lady and hypnotizes her while Leela dresses in the blond girl's dress and puts the blond girl in a cupboard in Chang's room, dressed in her Leela outfit. Chang returns to the room and takes Leela, now disguised as one of the girls and the cleaning girl.

The Doctor and Litefoot are with a driver of a small boat, all three in it and sailing the Thames. The Doctor used to enjoy messing about in boats. Litefoot worries that the rifle, which hasn't been fired for 50 years, will explode in the Doctor's face. The Doctor thinks that is nonsense -- the elephant rifle was made in Birmingham -- it won't misfire, ever! The boatman ties the boat up to a wall where the Doctor plans to enter the sewers.

Weng-Chiang inspects the girls and finds Leela has muscles like a horse. Once he gets the time cabinet, he can move from this place. He puts the cleaning girl in the distillation chamber as he calls it. He grabs Leela's face in his clawed hand, "I won't keep you waiting long."

Entering the sewers, the Doctor calls back Litefoot, telling the Professor to wait for him for only two hours, also telling him if he is here when the tide is at high not to bother.

Weng-Chiang has started the distillation chamber and the cleaning girl vanishes in a blaze of power. Leela has slipped out of her dress and uses a piece of cord to choke Weng-Chiang from behind. She drops him and turns off the machine. The cleaning girl reappears but Leela sees her body is parched black so feels her pulse. She is dead. Weng has picked up a laser gun pistol to fire at Leela, knocking her off a ladder she was climbing to escape. Leela falls off it but manages to get out under the bar gate leading into the sewers. Weng-Chiang hits a gong and closes the cover over the bar gate. This summons the giant rats.

Two Chinese men arrive to deliver laundry to Litefoot's house and remove the old laundry, both old and new laundry being in a wicker basket.

At the Palace Theatre, the blond girl leaves Chang's room and goes downstairs where she encounters Casey, who thinks she is nicking things. Jago arrives. The blond cannot remember much but when she sees the poster of Chang on the wall, she blames him and runs outside. Jago tells Casey he has made the acquaintance of someone very high up, an amateur investigator called in by Scotland Yard.

In the lower sewer chamber of Weng-Chiang, Li H'sen Chang has figured out that it was Leela who attacked Weng. He thinks she must have traded places with her and that the Doctor sent her to attack. Weng feels Chang has made too many mistakes and dismisses him. Chang doesn't accept this and bows to him, calling him master but then leaves, climbing up the ladder, vowing to get the Doctor next time. Weng turns on the machine which Leela shut off. He has the cleaning girl's life force flow into him, making him feel a bit better.

The Doctor blasts the rat chasing Leela but Leela passes out briefly, the dead rat on her leg. She is only bruised but tells the Doctor she deserves death -- she failed to kill their enemy Weng-Chiang. They hear another giant rat and since the gun takes one half an hour to load, the Doctor suggests they leave.

At the Palace Theatre, Jago and Casey discuss money problems which were brought up by Mrs. Samuelson, someone who does their costuming and handles the cleaning staff. Chang arrives, Jago joking he should charge him rent. Chang tells him that tonight he will have to appear without Mr. Sin -- who Chang claims is indisposed. Jago laughs that is droll but adds his own joke, telling Chang perhaps the little Sin has a touch of woodworm. Chang smiles at this.

At Litefoot's house, the Doctor and Leela talk. Leela tells him the dead girl had dry skin like old leaves after the machine killed her. The Doctor believes it to be the organic distillation process -- sucking the life essense from the girl into Weng-Chiang. Leela tells the Doctor that Weng-Chiang seemed to know what he was talking about. The Doctor wonders about some kind of key which, with the correct molecular combination, can open the Time Cabinet. Litefoot arrives to the room with new clothes for Leela -- which he picked out. Leela starts to change in the room but Litefoot tells her to go upstairs where Mrs. Hudson will help her change. Leela leaves the room. The Doctor explains more to Litefoot. When Leela arrives in her new dress, the Doctor is stunned. He would be proud to take her to the theatre and if she is very good, he will buy her an orange.

Casey and Jago return to the theatre from Mrs. Samuelson's, discussing money matters. Casey, innocently, comments that Mr. Jago doesn't do anything. Jago backs himself up, telling Casey he introduces the acts, counts the tickets, and smiles at the people -- all very taxing indeed. Jago asks Casey about the Doctor, his collaborator and fellow sleuth, commenting the Doctor is coming to the show tonight. Behind a partition, Chang overhears this, returns to his room, and loads a pistol.

Back at Litefoot's house, Leela plays chess with the Doctor as Litefoot returns, telling them it is thick out and they will need their coats. Police are outside, watching the house. The Doctor wins the chess game. Litefoot comments the ruffians won't catch "George Litefoot napping a second time." The Doctor and Leela leave, the Doctor telling the cabby to make it snappy. Litefoot bolts the door behind them.

In the lower regions, Weng-Chiang is packing a large carpet bag. Chang comes down to him, telling him the Doctor will be here tonight. Weng-Chiang thinks it more likely the Doctor will kill Chang when Chang tells him he will kill the Doctor. Weng dismisses Chang again, "You no longer serve me."

The Doctor and Leela arrive at the theatre and are seated in a balcony. Casey and Jago see them. Jago explains the Doctor to Casey: he is a man of a thousand faces, isn't likely to be dressed like a detective, and has the woman along as mere window dressing. Casey doesn't think the Doctor looks like a detective. Jago sends Casey to the cellar to check on the trap door needed for Chang's act.

Jago goes to the balcony, crouching down so as to have no one see him. Leela looks at him puzzled by this strange man with the cigar. The Doctor tells Jago he expects developments soon. Jago knew he could rely on the Doctor who has no men in the audience. The Doctor tells him nobody -- he and Jago will face their destiny shoulder to shoulder. Jago doesn't sound pleased by this.

In his living room, Litefoot reads Blackwood's Edinburgh Magazine. He gets up to look outside the curtains and he sees the policeman walking his beat outside his door.

Leela and the Doctor watch a singing act -- a woman singing "Daisy". Leela asks about the responses as the crowd sings along with the woman. The Doctor tells her they are not obligated to respond.

In the basement under the stage, Weng-Chiang comes up a trap door and moves toward Casey from behind. Casey turns and sees the claws of the monster coming at him. He is too terrified to scream.

Jago takes the stage to introduce Chang after making some lame jokes about the previous performer. Chang, Jago states, entertained all the crowned heads of Europe and has an extended season of appearances here -- there will be two tonight. There is a blast and Chang appears on stage. A servant boy brings a box, from which Chang pulls a blanket out of and makes it blast away. For his second trick, he takes out a deck of cards and asks for a volunteer from the audience, settling on the Doctor's area. He throws the cards to the Doctor.

The Doctor catches the card deck and takes out one card, showing everyone -- the Ace of Diamonds. He returns the card to the pack and holds up the deck between his fingers and thumb as Chang instructs. Chang will use his magic bullet to shoot through the Ace of Diamonds card only without hitting the other cards. Chang urges the audience to be quiet as he killed 50 peasants learning this trick. Leela turns at the Doctor as Chang points the gun at him. The Ace is shot. Chang needs the Doctor to demonstrate the next trick: putting the Doctor into a human sized box and shoving swords through it. The Doctor is supposed to be unharmed within.

Two Chinese men move up on Litefoot's house, one carries a strangling rope, the other an axe, which he uses to kill the policeman by hurling it into his back. Litefoot drops his book... asleep. Mr. Sin comes out of the wicker basket and walks the hallway toward the living room.

On stage, Chang demonstrates the box is solid on all sides -- calling it the Cabinet of Death. The Doctor is closed into it and the cabinet is turned all ways around and around. Before anything else can happen, the Doctor merely walks out the back of the box, making the audience laugh. Chang instructs the servant boy into the cabinet. Chang gets swords, handed to him by someone beyond the black curtains. He sticks them into the cabinet of death one by one. The servant boy climbs down to under the stage via the trap door and out of the Cabinet of Death. He bows when he sees Weng-Chiang standing over him. Above, on stage, Chang calls this trick the Death of A Thousand Cuts, finding it is the Doctor handing him the swords. Chang instructs the Doctor to open the cabinet and inside is a wide eyed and very dead Casey, who falls out. Jago orders the curtains dropped and sees it is Casey, "Poor fellow, he's worked here for years." The Doctor noticed that Chang was just as surprised. Chang has slipped off, calling for his master, Weng-Chiang. The Doctor finds Chang and before he can take poison, the Doctor knocks it away. Leela sees that Chang's mind is broken. The Doctor knows now that Chang knows Weng-Chiang is not a god. Chang admits he thought, at first, Weng-Chiang was the god. He gave Weng sanctuary while the soldiers of Tung Chi searched for all. The soldiers found the cabinet and took it; afterward it was given away as a gift -- to Litefoot's family. Jago comes down a ladder, distracting Leela and the Doctor momentarily and accidentally. This gives Chang a chance to escape under the gates to the sewers. He lowers the door cover down. The Doctor stops Leela from following this time -- Chang has gone to join his ancestors.

In the sewers, Chang runs from the rats.

Jago cannot believe Mr. Chang was involved in all these Machiavellian machinations. He, Leela, and the Doctor hear Chang's loud scream as a rat starts on his leg, downing the man first.

Leela finds the dresses of the former victims -- now all that is left of them are these dresses. The Doctor tells Jago that the only way to kill off the rats is probably cyanide gas but the sewers will have to be shut down for a few days. Leela notes the machine of Weng-Chiang is gone. The villain will start up somewhere else. The Doctor explains more: Weng's DNA helix is split open so that more and more cells are being absorbed, causing him to be deformed more and more. Leela likens it to a waterbag which has a hole in it and the hole is getting bigger. The Time Cabinet did this to Weng -- it is a dangerous time travel experiment device. Weng is working hard to keep his metabolism in balance, it being knocked off kilter by his unstable time device -- the Time Cabinet. Leela asks about the rats; the Doctor figures they were needed for a psionic amplification field and later, for sewer guards. Jago thinks he can make a fortune off of all this. The Doctor and Leela climb up the ladder. The Doctor tells Jago, he has things to do. Jago hears a rat roaring and runs up after the pair.

There is something howling as Weng-Chiang's coach pulls away from Litefoot's house. Leela and the Doctor find the dead policeman. They rush into Litefoot's house and find the laundry basket open. Litefoot is recovering as the Doctor yells and rushes in, expecting a fight; Leela takes off her straw hat. Litefoot tells them dozens of Chinese men were in the house and took the Time Cabinet. The Doctor makes Leela get Litefoot a drink -- in a glass, not from the bottle. The Doctor goes out and looks at the basket, realizing Sin came in that way, telling Litefoot, "Elementary, my dear Litefoot." The midget is not a normal human being: it is the Peking Homunculus which was made for the children of the Commissioner of the Icelandic Alliance in another Ice Age around 5000 AD. It was a toy, a plaything with a small computer inside but had one organic component -- the cerebral cortex of a pig. It almost started World War Six. The pig part took over; Weng-Chiang brought it back through time -- it was never found. It is about unsuccessful time travel started by someone named Findicus, whose experiments lead science down a cul-de-sac -- a dead end of failed time devices, which only partially worked. It needed a human operator but the mental feedback was so intense, the swine instincts took over. It hates humanity and revels in carnage.

In a new hideout, Weng-Chiang tells Sin they now have freedom. Soon, he himself will be whole and alive. Chinese men come and bow to Weng but he discovers they do not have the carpet bag which holds the round time key to the cabinet. Weng makes the young servant, whom he told to guard the bag, take the sting of the scorpion. He dies in great pain and with his eyes open to the tune of the laughter of Mr. Sin and Weng-Chiang.

At Litefoot's house, the Doctor finds an address card on the side of the laundry basket.. .a bad East End area between White Chapel and Saint George's. Litefoot always thought it should be cleaned up. The Doctor thinks it may be cleaned fairly quickly -- Weng-Chiang is a scientific ignoramus; his power source is the Zigma Beam which is stretched to maximum; if he operates it again, he could vaporize a great deal of London. When the Doctor makes Litefoot wait here and suggests to take Leela, Litefoot protests -- she will see depravity and vileness in that area of the city. The Doctor takes Leela out with him anyway, telling the white haired Professor there is nothing more vile than Weng-Chiang himself.

In the cellar lair, Jago is once again pondering on what a fortune he will make, charging a shilling a head for customers to see the phantom's lair. He finds the carpet bag, not noticing a bloody hand coming up from a trap door.

At the East End laundry, Leela and the Doctor slip through a low level roof window. The Doctor tells her to be quiet. He trips and makes a loud crashing sound.

Jago brings the carpet bag to Litefoot's house, having inquired in the local station as to where the Professor's house was -- he knew the Doctor and Litefoot were seen together in town. Jago, at first, mistakes Litefoot for the servant, telling him to get his employer. Litefoot introduces himself and to make up for his mistake, Jago boasts of Litefoot's greatness -- his noble brow, his sturdy hands, "England's premier professor of pathology." Of the Doctor, Jago admits he probably solves one half of the cases of Scotland Yard but lets them take the credit. Jago figures this because, while he likes the police of the Yard, their buttons are the brightest things about them. He also calls the teaming of the Doctor and Litefoot, formidable. Litefoot thinks, since the bag was left behind at the Palace Theatre, he and Jago should keep a discreet watch on the place. When the cretins come back for it, they can follow them to Weng's new lair. Jago grows fearful -- the nocturnal vapors do bad things to his chest. They will leave a note for the Doctor. Litefoot has some lumps to repay the Chinese men who attacked him.

At the laundry place, the Doctor puts a piece of paper under a door and then uses a pin to push a key out of a door onto the paper. He then pulls the paper back into the room, a part of it still remaining under the side that he and Leela are on. This gets them to open the door and into the building. Leela smells opium, a narcotic drug, which she claims smells like dead fruit. It seems no one is here. The Doctor wonders where Weng-Chiang is. A voice says, "At the House of the Dragon." It is Chang, horribly injured and sitting in a corner on some blankets and smoking opium. He feels nothing. Leela notices his leg; the Doctor moves to look at it to help him but Chang tells him it is too late for him. He was brought by the rat to a charnel house, human remains, left for later consumption. When he awoke, he cursed Weng-Chiang and the hatred of his former master and "god" gave him the strength to pull himself to safety to seek vengeance. He wants to destroy this false god. Leela says, "You should have done that before." The Doctor figures Weng put on a good act and feels somewhat sympathetic to Chang. Or perhaps he needs Chang's help.

Chang start to ramble about being the poor son of a peasant who will soon entertain the Queen Empress at Buckingham Palace. He also says he sees his ancestors coming to greet him from the Palace of Jade, the ancestors carrying fruit and flowers as gifts. He will, in seconds, cross the bridge to meet them. He touches the shoe of the Doctor, telling them to "beware the eyes of the dragon." He also leaves the shoe clue, which the Doctor and Leela cannot figure out -- shoe, boot, earth? A Chinese puzzle, the Doctor says as Chang cannot explain further... he is dead.

At Weng's place, the House of the Dragon -- a Tong Headquarters -- Ho reports that the carpet bag is gone from the former hideout. Weng-Chiang, in his ranting, spots Jago and Litefoot from a window. The two are down below, in the street, having followed the Chinese men from the Theatre. Weng orders them taken. Litefoot thinks one of them should go get the Doctor and bring him back here. Jago tells him he'll be as quick as he can... Suddenly, they are surrounded by the Tong. They back up against the wall, ready to fight. They are dragged to Weng-Chiang, who slaps Litefoot when he knows the man is lying to him about what the bag is and where the bag is. He also starts to choke Jago and will kill him unless Litefoot tells them where the bag is. Litefoot gives in and tells him. Chiang lets Jago go and tells Litefoot that later, they will please his wolves by being their meal.

The Doctor and Leela arrive back at Litefoot's house where the Doctor finds the note from Jago on top the bag. The round time key, the trionic lattice is a part that the Chinese Tong will return for...Weng-Chiang needs it. The Doctor finds it in the bag. Leela wants to look for Jago and Litefoot, "Professor Litefoot and Mr. Jago are our friends. We must help them. You know what Weng-Chiang will do to them." The Doctor thinks they should wait here. They have no chance of finding them in the entire city -- Litefoot's fire has gone out, meaning he has been gone a long time. He thinks they should wait for Weng-Chiang to come to them. Leela realizes, now, the Doctor has a plan. She wants to set an ambush, "It is time we did battle with this underground crab, Doctor." She sharpens a knife.

In their holding room, a locked room in the House of the Dragon, Jago and Litefoot find two young girls, not a day over 16 Jago reckons, who are unconscious, and who are to be used as more life force for Weng. Litefoot wonders what unspeakable horror lies behind Chiang's mask. Jago hopes the Doctor will find them. The two men find a dumb waiter and get in. They hope to get out through the dining area but end up in a dark, large room -- the throne room with the gong. There is a statue of a giant dragon as well as more of the Tong, ready to take them prisoner again with a variety of weapons.

One of the Tong take Leela, who passes out from the chloroform. The Doctor returns to the drawing room and sits down, talking as if he is talking to Leela but finds Weng-Chiang sitting next to him, glad the masked man showed himself in. Weng asks for the time key in return for sparing Leela. The Doctor starts to empty his pockets, declaring with a smile that he is always borrowing things from people, then forgetting where he puts the things. Weng has never appreciated frivolity as such as this. The Doctor takes out what looks like a yo-yo, a kazoo harmonica, a turtle shell, and a small plastic sander machine. Weng points at him and the Doctor says, "Never trust a man with dirty fingernails." The Doctor eats jelly babies. Weng wants it and the Doctor asks if he means a jelly baby. Weng has had enough -- he orders Sin to kill the girl but the Doctor bends down behind the table and comes up with the time key. Weng makes Sin back off Leela. The Doctor will give the lattice circle to Weng at the House of the Dragons. He tells Weng that two other of his friends are being held and he wants them released. Weng calls the two blundering dolts. The Doctor doubts Weng-Chiang could understand why he wants them released.

Leela is left on the floor, dropped by one of the Tong. The Doctor makes Weng-Chiang and all his men and Sin leave ahead of him. He follows, threatening to smash the time key if they try anything. Leela picks herself up and begins to follow.

At the House of the Dragon, Jago and Litefoot have been put in the room again. Litefoot mentions it will be dawn soon, giving Jago more cause to worry about what that may signify. He thinks they might, you know, do things at dawn, such as sacrificing victims. Litefoot tells him he is thinking of the Druids. Jago is glad -- it's been worrying him. He tells Litefoot he is not bloody brave when it comes to it, even though he tries. Litefoot tells him that when it comes down to it, no body really is. When Jago expresses concern that he will let the side down, Litefoot knows Jago will not let them down.

The Doctor realizes Chang's clue was about the tongue of his shoe -- the Tong. In the House of the Dragon, the Doctor orders soup from a bemused Weng-Chiang. Sin is put down but sneaks up into the dragon statue and sits behind the controls of a laser device. The Doctor calls Chiang's experiments "buckam" and "cannibalism". The Doctor know everything about Weng-Chiang's time, having been with the Filipino army in their final advance on Reykjavik in the 51st century. Sin lights up the dragon's eyes. Chiang tells the Doctor his real name -- Magnus Greel, the minister of justice, also called the Butcher of Brisbane. The two move over to a chess game where the Doctor finishes it by beating Greel, who throws the pieces down. The Doctor knows Greel caused 100,000 deaths -- which Greel called enemies of the state. They were slaughtered in Greel's filthy machine. Greel tells the Doctor that it is the winning side that writes history and that he made time travel possible for the Doctor, mistakenly thinking the Doctor is a human from the future time -- the 51st century.

Sin, anxious to kill, snorts like a pig from behind the eyes of the dragon.

Jago and Litefoot are brought out to reunite with the Doctor. Jago bluffs that the whole place is surrounded by the police, who followed them. Litefoot mentions the two girls; the Doctor wants the two men to take the girls with them but Weng-Chiang yells that the Doctor's demands have become too much. He orders Sin to fire. Sin gets one shot at the Doctor, who falls, "Beware the Eyes of the Dragon." The Tong men take the trio away to the prison room.

Leela chokes a Tong man from behind and turns him around into a curtain, killing him. She gets into the House of the Dragon.

In the throne room, Sin is eyeing Greel through the viewer of the dragon eyes, wanting to shoot someone. Greel uses the time key to open the cabinet.

In the prison room, Litefoot listens and hears the Doctor's double heart beat. The Doctor gets up and asks them to help move the girls and to break a gas pipe. He also asks the two men to fetch him a bucket of water.

Weng notices Sin, attributing Sin to sulking because he wouldn't let him kill the Doctor. Weng or rather Greel, tells Sin that he can kill the Doctor after he gets all the Doctor's knowledge about the Zigma Experiment. Greel must balance his own protonoids and program his DNA levels. Greel hits his gong just as Leela jumps out at him from behind; she intends to plunge the knife into his neck as he pleads for mercy. Tong men arrive and pull her off. Weng almost stabs her but has a better idea. He has her put into the distillation machine. As he spouts hatred at Leela, she tells him if she does die, she will hunt him down in the hereafter and make him feel her agony 1000 times over.

In the prison room, Jago claims he hasn't been worried since the Doctor showed up. The Doctor tells the girls, who are now awake, that if they manage to get out of this place, not to stop running until they are a mile away or more. Using a pillow and some rags as well as water and the gasoline, the Doctor has made a gas bomb which he detonates when four or five Tong men come to the door. The Tong men fall from this and the Doctor takes one of their axes. The girls run out.

Leela is in the machine in the throne room and gagged now. Greel rants at her, telling her she will now feel the Talons of Weng-Chiang shred her flesh. He starts the machine. The Doctor rushes in, yelling at Greel and flyings the axe at the control panel of the machine. It sparks up and the Doctor pulls Leela out. Greel orders Sin to kill everyone in the room. As Sin fires the laser beams from the eyes of the Dragon, Jago, Litefoot, Leela, and the Doctor take cover behind a bench. Greel offers to let them go to be rid of them but they don't believe him, Leela telling them he has no truth in him. The Doctor thanks him anyway, "That's awfully magnimous of you, Magnus." The Doctor looks up and has his hair singed. Greel orders Sin to cut away the bench they are hiding behind. The bench starts to get blasted away piece by piece. Jago mentions something about being good at the catapult when he was a nipper. The Doctor directs the other three to turn the bench over with him; then slips off to the side. Tong men come running into the room, ready to kill them from behind but Sin laughingly cuts them down with the laser, killing the Chinese men. The Doctor tosses the axe into the middle of the Dragon's head, hoping to get Sin. Leela shows Jago a fallen revolver from one of the dead Tong men. She wants him to distract the fire of the eye laser fire while she gets it -- because she is quicker. Jago doesn't think it can be done but distracts Sin's fire by jumping up and yelling. Leela gets the gun and Jago is grazed by the laser but is okay. Litefoot has him. Leela gets to a cabinet and shoots at Sin but almost hits Litefoot. She tells him she has never fired one of these guns before. The Doctor is making his way closer to the cabinet as Sin even starts to try to kill Greel with the laser. The Doctor tries to make Greel listen to reason, telling him if he activates the Zigma Beam, it will collapse, there will be an implosion, and all will die with Greel at the center. The Zigma Experiments were a disaster, he tells Greel. Leela jumps out as Sin shoots at Greel, who stepped into a close range of fire. Leela manages to disable the deadly laser eyes but Greel has a gun now, too. He points it at her but the Doctor grabs Greel and throws him into the open Time Cabinet. There is a blast and all the others can see is the back of Magnus Greel. Leela stops Litefoot from reaching for Magnus's back. Magnus's cloak and outfit collapse to dust and nothingness. Litefoot and Jago yell as Sin jumps off the dragon onto Leela's back. The Doctor pulls Sin off her but it gets onto his back. He lifts Sin up, off himself and twirls him around. He knocks Sin down and pull out a long fuse from Sin's back. The Doctor brings the Zigma Experiments to an end by stepping on the Time Cabinet's Key -- actually a crystal.

It is morning by this time and the Doctor hears the sound of the Muffin Man. The Doctor says he will buy them all muffins. They move out of the House of the Dragon.

Later, in the fog and at night, Litefoot accompanies Leela back to the TARDIS while Jago is with the Doctor, behind the two. Litefoot is trying to teach Leela about tea, telling her if someone asks her for one lump of sugar or two lumps, she should always answer the expected answer of a lady -- one lump. She asks what if she wants two. Ladies always take one, he answers. She shrugs, "Then why ask me?" Leela tells the catching up Doctor that Litefoot is teaching her about tea, "It is very complicated." The Doctor and Leela bid their goodbyes to their two friends; the Doctor telling Jago, "It's been such fun." The Doctor continues to try to explain about tea as he and Leela go into the TARDIS doors and shut them.