The TARDIS lands in a quiet wood. On board, the Doctor announces that he has brought Ian and Barbara home and is anxious for them to leave. Ian is understandably sceptical that this is home, but is resigned to leaving. Susan hugs them both then runs sadly off into the ship.

Ian asks if the Doctor has run the checks to determine if it is safe outside, but the Doctor is adamant. He turns on the scanner and shows them the woods and, beyond, crops. But no buildings. Barbara surmises it might be Somerset. The Doctor repeats his desire for them to leave so he can be off. Ever cautious, Ian flatters and cajoles the Doctor into seeing them off outside. He wants to make sure that this is the right place. Susan fetches the Doctor's walking stick and the four of them venture out.

It is a warm summer evening outside, and the landscape is clear. Barbara thinks this is a farm and they set out in the likely direction of a farmhouse. But they haven't gotten very far when they hear movement in the bushes. Ian flushes out and catches a very frightened young boy. He is dirty and disheveled. The boy tells them that they are in France, 12 km from Paris. But before they can find out the date, he bolts and is gone.

The Doctor is proud of his landing, very near England in relation to the distance travelled, but Barbara believes that they are years out as well as miles. Neither she nor Ian are terribly upset at not being home just yet. The four set off in the direction the boy went.

The boy reaches the farmhouse, knocks on the door, and is let in. The travellers approach the farmhouse and are dubious, as it looks empty and rundown. The Doctor finds an open door and they all enter. There is dust everywhere, but also some very nice candlesticks looking out of place. The Doctor heads upstairs to investigate and is promptly knocked unconscious by an unseen assailant.

Susan discovers a trunk in a corner and all three investigate. There are several sets of clothing in different sizes, parcels of food, and some blank documents -- passes waiting to be forged -- indicating that this place is a way-station in some escape chain. The signature on the passes is that of Robespierre. This is the time of the French Revolution - the Reign of Terror.

Ian, Barbara, and Susan change into some of the period clothes to look inconspicuous on their way back to the TARDIS. Ian calls for the Doctor, but there is no response. He goes upstairs to search, but the doors are all locked. As he returns, he hears a scream from Susan.

Two men, D'Argenson and Rouvray, hold the girls at gunpoint. Ian is soon a prisoner as well. They try to explain that they are travellers and have no sympathies with either side in the conflict, but the nervous D'Argenson does not believe them. Rouvray is more clear-headed and accepts their word. Ian then lies when asked if anyone else was with them, setting D'Argenson off again. They were the ones who knocked out the Doctor and imprisoned him upstairs. But before Rouvray can question them further, soldiers arrive outside and they are trapped.

The soldiers are a ragtag group of citizens - peasants really - who have been forced to join the army. Most are only in it for the sport, including one soldier who only reluctantly agrees to cover the back of the house. The sergeant surrounds the place, attempting to break the nerve of the men inside.

D'Argenson's nerve is already near the breaking point and he waits agitatedly while Ian and Rouvray try to think of a way out. Rouvray realizes that the soldiers must have followed them. They have been betrayed by a traitor in their organization. But who? Before the others can think of an escape plan, D'Argenson suddenly snaps and runs outside. Rouvray rashly follows in loyalty to his friend.

The soldiers hold both of them at gunpoint, but it turns into a war of nerves between Rouvray and the Sergeant. Rouvray, a former army captain, orders a soldier to hand over his gun and he does so, challenging the authority of both the sergeant and the harsh government he represents. D'Argenson runs and is gunned down, followed by Rouvray.

The soldiers enter the house and capture Ian, Barbara, and Susan. The sergeant barely restrains his men from killing them. He explains that while they have done their duty in killing the two royalists, they also want credit for catching others. Besides, the guillotine will kill them much more spectacularly. The prisoners will be marched to Paris. Before they leave, though, the men set fire to the farmhouse.

Susan is almost hysterical, fearing her grandfather trapped inside as the house goes up in flames. Ian, knowing they can do nothing, says that they must simply hope he has escaped... for all their sakes.

As the prisoners are marched away, the young boy watches from hiding.

The roof of the farmhouse caves in and the flames reach higher. The Doctor is unconscious and trapped.

In Paris, Ian, Barbara, and Susan arrive at the Conciergerie Prison and come before a kangaroo court. They are not permitted to speak in their defense and because they were found with D'Argenson and Rouvray, they are found guilty. All three will be guillotined as soon as it can be arranged.

Ian is then placed in one cell, and Barbara and Susan are taken to another. The jailer, an ignorant drunk, offers to ease Barbara's imprisonment if she will just "be nice" to him. She slaps him in response. She and Susan are then placed in the worst cell in the prison. As the door is locked behind them, despair begins to grip Susan as she fears her grandfather is dead. Barbara is sure he has escaped, but Susan believes that their past escapes have been due to luck. And she fears their luck has run out.

But Barbara is right. The Doctor has escaped, with the help of the young boy they encountered in the woods. The Doctor comes to outside the house the next morning. The boy, Jean Pierre, gives him water and tells him what happened. He overheard the soldiers and knows the Doctor's friends were taken to the Conciergerie Prison. The Doctor heads off for Paris immediately.

In their cell, Barbara and Susan search for a means of escape. But the despair takes tighter hold of Susan. Barbara fashions a crowbar from part of the bed frame and attempts to remove a crumbling stone from the wall.

In Ian's cell, he tries to help make his cellmate more comfortable. The man, and Englishman named Webster, has been shot by soldiers and has lost a lot of blood. Webster tells Ian that the English government believes that the political situation here in France will stabilize someday soon, and then France will turn its attention toward England. There is an Englishman undercover, high up in the French government, who is gathering evidence of this. It was Webster's job to find him and return him to England. Now Ian must do this - find James Stirling and tell him to bring his information back to England right away. As Webster fades away, he tells Ian to find Jules Renan at the sign of "Le Chien Gris" to get to Stirling. Then Webster dies.

The Doctor, on his trek to Paris, comes across a road crew. The leader shouts and bullies his men - tax dodgers forced to work off their debts - and the Doctor does not suffer this fool gladly. However, the Doctor's sharp tongue rouses the leader's anger. With no identity papers, the Doctor is forced to join the road crew.

Barbara is making progress with removing the stone. She stops to take a rest and Susan takes over. However, the jailer arrives with food and they are barely able to cover the hole with a blanket in time. The jailer is appalled to see the blanket on the grimy floor and goes to retrieve it. He is stopped when an authoritative voice calls for him.

Lemaitre, a government official, looks over Webster's body. He pulls the blanket back over him and then asks Ian if Webster spoke. Ian lies and says no. Outside the cell, the jailer swears he heard the two men speak, but did not hear what was said. Lemaitre then crosses Ian's name off the execution list.

The Doctor has had enough of toiling and comes up with an escape plan. The other members of the crew go along with him as he stops work to look for "an eclipse" which is soon to happen. The Doctor uses this distraction to steal a handful of coins from the crew leader's purse. When the crew goes back to work, the Doctor tosses the coins into the hole they are digging. He then loudly "discovers" the coins. The crew leader, greedy as well as boorish, pushes off the men and starts to dig on his own. The Doctor then knocks out the leader with a shovel. The crewmen flee and the Doctor heads on to Paris.

Susan starts to take another turn with the crowbar, but is frightened by rats emerging from the hole. Her will collapses and she will do no more work. They are stuck where they are.

The Doctor is still 5 km away from Paris when the two women are taken from their cell and lined up with the other prisoners to be executed. They learn that Ian has been spared as they are led out to the guillotine.

As Barbara and Susan are led out of the prison, the Doctor arrives in Paris.

Barbara and Susan are loaded onto a cart to be wheeled to the guillotine. Nearby, two men - Jules and Jean - await the cart to effect a rescue. They are old hands at this and worry because the cart seems to be late in arriving. They are also concerned by the absence of their friend Leon. Despite their concerns, they decide to wait a little longer.

At the prison, the jailer brings round food to the prisoners. He approaches Ian's cell, unlocks the door, and slides the food bowl in on the floor. He then goes to relock the door, but he is distracted when Lemaitre's voice booms out demanding the jailer's attention. The key gets stuck in the lock and the jailer cannot remove it. Not wanting to keep Lemaitre waiting, he leaves the keyring hanging in the door and runs off. Lemaitre demands the execution figures which he will be taking to First Deputy Robespierre. The jailer produces them and Lemaitre looks them over, telling the jailer idly that he hopes for his sake that the figures are complete.

Ian, going to pick up his food, notices the key in the keyhole and looks out the cell door's window. He sees the keyring and immediately reaches for it. He manages to remove the key from the lock and bring the whole ring into his cell. Not wanting to arouse suspicion, he takes only the key for his cell, then replaces the ring, jamming another key into his door's lock. Then he sits down to eat, waiting his chance to escape.

Lemaitre finishes reading the list and flatters the jailer at his fine work "for the cause". He says that he will make sure the jailer's name is mentioned "in the right circles" as a reward. The jailer is pleased with himself as Lemaitre leaves. He remembers the keyring and hurries to Ian's cell. There are the keys, just as he had left them. He removes them and shuffles off.

Out in the streets, the cart carrying Barbara, Susan, and the other prisoners comes to a halt. It seems the horse has thrown a shoe. Barbara sees this as their chance to escape, but Susan has become very ill and cannot move. Nearby, two townswomen laugh evilly at their plight.

Jules and Jean find the stopped cart, having finally gone in search of it. When one guard takes the horse away, they have only four guards to fight and are pleased. They attack the guards, shooting all four. The other prisoners run, but the two men grab Susan and Barbara and lead them to safety.

Meanwhile, the Doctor arrives outside a tailor's shop. He inspects it for a moment, and then enters. The tailor is an obsequious little man and an overly attentive shopkeeper. He is extremely interested in today's executions, which he sadly had to miss. He extols the virtues of Robespierre and the duty of all citizens to ferret out traitors. The Doctor cuts to the point and asks if the Conciergerie Prison is nearby. The tailor shows it to him through the shop window.

The Doctor looks through the garments on the rack and spots a coat as well as an official-looking sash. The tailor explains that it is the garment of a Regional Officer of the Provinces. The Doctor says he knows, as he holds that position. As he tries on the coat, he mentions he has no money. The tailor refuses to let him try anything on, but the Doctor wants to barter his clothes for the new ones. The tailor refuses him, but spies the Doctor's ring and asks for that into the bargain. The Doctor reluctantly agrees, but also secures parchment and writing materials to complete the deal.

Susan and Barbara arrive and Jules' house. Jules tells them that all of the servants are gone, as that is safer. A young woman, Jules' sister Danielle aids them by preparing food and a bath. Jean goes off to help her. Jules refuses to offer his surname, as that is safer. If captured, his confederates will have less to confess that way. He tells the girls that they will be given food and a place to rest, then they will be smuggled out of France. Barbara and Susan protest that they will not leave without the Doctor and Ian.

At the prison, as evening falls, Ian makes good his escape. He unlocks his cell and tiptoes quietly through the corridors. However, he has been helped along. The jailer has been knocked unconscious. Ian does not pause long, heading quickly out of the prison. As he leaves, Lemaitre watches him intently, musing out loud weather Webster talked to him or not.

Back at Jules' house, their meal is finished and Jules reminds Barbara that she promised to tell him their story. He brings out a map and they show him where they arrived and the farmhouse where they were arrested. Jules is concerned and brings Jean in to look at the map. Jean asks if they met two men at the house. When Barbara says yes and identifies them as D'Argenson and Rouvray, Jules and Jean realize that someone has discovered their escape route. When she tells them that D'Argenson and Rouvray were killed, they worry over the safety of their absent friend Leon. Jean reminds Jules that this is not the first time their compatriots were compromised. They rescued D'Argenson and Rouvray the same as they rescued Barbara and Susan. Now they are dead. Jules promises to sort this out. He will send someone to the farmhouse to find the Doctor and will inquire at the prison after Ian. He says he will not rest until the four of them have been reunited.

The excitement worsens Susan's illness. She is feverish and faint. Danielle takes her upstairs to rest just as there is a knock at the door. It is Leon. Their reunion is short-lived as Jules and Jean explain about D'Argenson and Rouvray. Leon is concerned about this, but also about a stranger who is in Paris asking for Jules. He and Jean leave to find the person. Leon is immediately takes a fancy to Barbara and the two share a toast.

At the prison, the jailer is recovering from his headache with a large bottle of wine just as the Doctor blusters in, fully outfitted as a Regional Officer from the southern province. He presents his bogus credentials and blusters about not being met on his arrival. When the jailer attempts to placate the Doctor, the Doctor knows he has found the person who can provide him with information. He asks about three "traitors" who were brought in earlier. The jailer explains that the woman and the girl were taken to be executed but were rescued by unknown parties. The jailer is quick to explain that it wasn't his fault - that he's "surrounded by idiots". The jailer then explains that the man escaped and tells an incredible story of a fight for survival against him. The jailer says he risked his life but that the man fought with the strength of ten men.

The Doctor has all the information he needs and turns to go, only to be stopped by Lemaitre, who has overheard the whole conversation. He looks over the Doctor and his papers and seems satisfied. He asks the Doctor where he is going and the Doctor says he will head back to his province. Lemaitre however, insists that he stay until tomorrow. He says he is taking the execution lists to First Deputy Robespierre at this moment and that they will be discussing the Doctor's province. His input would be very valuable. The Doctor cannot refuse without incriminating himself and so leaves the prison with Lemaitre.

Back at Jules' house, Leon and Barbara talk. He asks her where she comes from. She says England and assumes that that makes them enemies. But Leon believes that means she has no interest either way in what happens in France. They share a moment together, and then Barbara excuses herself for the night.

At the Conciergerie Prison, the jailer speaks with the tailor, who has come to him with very important information. He produces the Doctor's ring and explains that he has evidence against a traitor...

Lemaitre and the Doctor enter First Deputy Robespierre's office. Lemaitre hands over the execution list and introduces the Doctor. Robespierre looks over the list and then expresses dissatisfaction with the progress of the Doctor's "province" versus that of Paris in finding and executing traitors. The Doctor, thinking quickly, turns the comment into a spirited debate about the state of France in general, avoiding specific talk of "his province".

The Doctor asks what benefit Robespierre sees in this reign of terror. For every traitor that is guillotined, two more spring up. Robespierre vows that he will do great things for France. The nobility were weak and did nothing to help the people. He asserts that the people are with him and no one wants to restore the nobility. The Doctor says they only say that because they want to keep their heads! Robespierre disagrees. He tells the Doctor that there have been 342 executions in Paris in just 9 days. That is progress. The Doctor says he does not want this for "his province" and that they will do things their own way. He then storms out.

At Jules' house, Susan has woken and come downstairs, but she is still feverish and very weak. Barbara, Danielle, and Leon tend her. Leon says that they need to call a physician to help Susan. Both he and Barbara agree that it is very dangerous, but Leon says he knows a person they can trust. He will go to him to see if he will treat Susan. He promises Barbara that they will meet again, soon. Leon gives her a gallant kiss on the hand and he is gone. She takes the weary Susan upstairs. Shortly, Jules and Jean return, carrying a body wrapped in cloth. It is the man who was looking for Jules. They ambushed and kidnapped him. They deposit him on the sofa and unwrap him. It is Ian.

At the prison, Lemaitre assures the Doctor that he made a favorable impression on Robespierre...even though they never discussed the Doctor's "province". The Doctor dismisses this and attempts to leave, but Lemaitre insists that the Doctor join him in another meeting with the First Deputy tomorrow. The jailer will show him to the soldiers' rooms, which will be his quarters for the night. The jailer tells Lemaitre that there is a man waiting to see him. It is the tailor.

While Lemaitre goes off to talk to the man, the Doctor attempts to bluff his way past the jailer, telling him it was initially his own idea to stay the night but that he has changed his mind. The jailer says he must obey Lemaitre and the Doctor must stay.

Lemaitre, meanwhile, has heard the tailor's story about the Doctor obtaining the clothing of a high official as well as parchment and writing materials. Lemaitre turns to go, but the tailor stops him, hoping to have the ring back. Lemaitre says he must hold the ring for evidence and pays off the tailor for his trouble. He also enjoins the tailor to silence, showing him out the back door.

At Jules' house, Ian starts to wake. Barbara enters and tells Jules and Jean that Leon is out trying to find a physician to treat Susan. She then sees Ian and is overjoyed. She tells him that Susan is upstairs but that they have had no word of the Doctor. Ian hears Barbara use Jules' name, and he asks if he is Jules Renan. When he says yes, Ian explains that he was looking for him and has some important information. Barbara excuses herself to look after Susan.

When Ian asks if Jules knew Webster, Jules says yes, but when he asks if Jules knows Stirling, Jules says no. Ian explains the conversation with Webster and "Le Chien Gris". They surmise that Webster must have counted on recognizing Stirling by sight. But how will they find him now? Jean says he doesn't want to be used by England as they are at war, but Jules says that it is the governments at war, not the people. When Robespierre's tyranny ends, so will the war. They must try to find Stirling to help end the war. Jean will go to the farmhouse to search for the Doctor and Leon will be contacted to help them find Stirling. He travels in a larger circle that Jules or Jean and may know something. Jules even muses that Leon may be Stirling himself.

Barbara returns, saying that Susan has gotten much worse. They must do something soon.

As morning dawns, the Doctor awakes in the prison. Lemaitre is waiting to greet him. The Doctor is upset at his poor accommodations, but Lemaitre is only interested in "the eventful day" ahead.

At Jules' house, Danielle brings a message from Leon: the physician won't come to the house. Susan must be brought to him. Danielle goes to get a carriage. Ian suggests that he goes with Susan, but Jules thinks it should be Barbara only. Two women travelling will be safer. Ian must wait here for Leon. Ian only hopes they can trust the physician.

Shortly, Susan and Barbara are at the physician's office. He says that Susan has a feverish chill and that she will be all right. However, he asks many questions about how she could have gotten such a chill. He is alluding to their possible stint in jail, but Barbara cuts across this to find out what he will do for her. The physician says all he can do is bloodletting, and he goes off to fetch leeches. The women must wait here.

As soon as he is gone, Susan is afraid and wants to leave, but they cannot. The door is locked.

The physician arrives at the Conciergerie Prison and talks to the jailer. He knows the two women are escaped prisoners. The jailer sends guards with him to arrest the girls.

Susan and Barbara wait nervously at the house. Soon the physician arrives with the soldiers and they are captured.

Back at Jules' house, Ian is convinced something has happened to them. They have been gone too long, and he moves to go after them, but Jules stops him. He agrees to go after the girls. He has received a message that Ian is to meet Leon at a nearby church. Leon has said he is not Stirling, but may know how to find him.

Susan and Barbara are brought back to the jailer. He will take great pride in informing Lemaitre of their return. Until then, there is someone who wants to question the prisoners. They are escorted into a side room, and come face to face with the Doctor!

Leon tells the captive Ian that there is no escape and no hope of rescue. Ian says that Jules will come looking for him if he's gone too long, but Leon assures him that he will "take care" of Jules. Ian goads Leon, calling him a traitor, but Leon does not rise to the bait. He offers Ian his freedom if Ian will tell him what Webster said. When Ian refuses, Leon leaves him under guard, to give him "time to think".

At the Conciergerie Prison, Barbara and the Doctor continue their joyful reunion. He brushes off questions about his escape from the farmhouse and inquires about Susan and Ian. She tells him that Susan had been ill but is feeling better now and that she is locked up. She tells him that Ian was last at the home of a man named Jules. She explains about Jules, Jean, and Leon. The Doctor knows that he must get the girls out of the prison and comes up with a plan. Barbara will escape first, but they must leave Susan there for her own safety for the moment and he will look after her. Barbara is pessimistic, but the Doctor reassures her that his plans always work out!

The Doctor goes to the jailer and asks for Lemaitre, but the jailer explains that he was called away some time ago by Robespierre. The Doctor tells the jailer that he has been interrogating Barbara and that she is a dangerous and influential member of the traitor party. She could turn over to them every traitor in Paris, but that she cannot be forced to talk. The Doctor says he cannot figure a way to get the information from her and turns to the jailer for help. Taking the Doctor's bait, he suggests that she be released and followed. They could see where she goes, who she meets, then arrest them. The Doctor is overjoyed at this suggestion and tells the jailer that Lemaitre will be delighted at his ingenuity. He leaves the jailer to unlock Barbara's cell door.

At Jules' house, he arrives back from the physician's office looking for Ian, but find no one there. Quickly, he heads off for the church.

At the church, Ian works to get out of his bonds but cannot. His guard taunts him mercilessly. When Leon returns, he again presses Ian to reveal his information. He says that his group has known of Stirling's presence for months and that he has been trying to find Stirling. Ian still won't talk. Leon presses on, talking of the way France was before the Bastille, the way the "high-born leeches" were draining France dry for their own gains and how he is helping to restore order. Still Ian is silent.

Sounding slightly desperate, Leon threatens Ian with the guillotine. Ian realizes that Jules has already told Leon as much as he knew - that Ian had a message to give to Stirling. Leon confirms this and wants more, but Ian reiterates that as he can't recognize Stirling, this questioning is useless. But Leon is convinced Ian is lying; that he has been part of the Webster's organization all along. Webster wouldn't have entrusted Ian with such a task otherwise. At the end of his patience, Leon demands to know the truth. And Ian tells him...about flying here in a small box and that when he left England it was 1963.

Just as Leon loses his calm, Jules bursts in. A fight ensues in which the guards are killed, Ian is wounded, and Leon is killed. After things calm down, Jules managed to tell Ian that Susan and Barbara were arrested at the physician's. They must risk going to the prison to try and free them.

At the prison, the Doctor comes to Susan's cell and she is overjoyed at the reunion. But he is forced to break off as the jailer returns. The jailer sees the Doctor and is horror-struck: he thought the Doctor was following Barbara after she was released. The Doctor says that he couldn't be inconspicuous in his regalia and that he thought the jailer would do it. The jailer thinks it obvious that a man in his position couldn't possibly leave the prison, but his protests come to an end when he realizes that Lemaitre will be furious when he hears what has happened. The Doctor reminds him that the plan was his idea and the jailer is scared for his life. However, when the Doctor presses his advantage and suggests the same plan for Susan, the jailer balks. He cannot possibly risk the escape of two prisoners in one day. He would be a dead man for certain.

Lemaitre arrives at Robespierre's office and finds the First Deputy oddly agitated. Robespierre explains that at the meeting of the convention tomorrow, certain influential members (whom he dubs traitors) will bring an indictment against another. He says he knows who they are but he will not be allowed to speak against them at the convention. He knows that the leader of the group is his deputy, Paul Barrass, and that Barrass is leaving Paris tonight for a secret meeting that will set in motion the indictment tomorrow. He orders Lemaitre to follow Barrass and find out who he is meeting and why. Lemaitre agrees, but asks why this is relevant. Because, Robespierre replies, the indictment will be against himself.

At Jules' house, he and Ian recover from their battle with the soldiers. Jules is quick to realize that this house will not be safe for long. If Leon told his confederates about him, they will come for him soon. They are both startled when Barbara arrives at the house, explaining that it was the Doctor who freed her (dressed in official clothes and acting, she says, as if he's "in charge of the revolution"!). She says that Susan is still in the prison, but that the Doctor will help her escape soon.

Barbara sees that Ian is wounded and asks what happened. Ian explains and Barbara asks about Leon. When Jules explains that Leon had to be killed to save themselves, and because he was a traitor, Barbara becomes quite angry. She had developed quite a fondness for him and saw him as a patriot, although it turns out now for the other side. She argues that the revolution isn't all bad and that history will prove this. Good people on both sides gave their lives and Leon was one of them, no matter what Jules and Ian try to say. She storms upstairs.

The Doctor goes to Susan's cell and orders her to lie on the floor hidden in a corner and not to move until he tells her to. The jailer returns to the Doctor saying that Lemaitre has not yet returned, but the Doctor is more concerned about the cell. Susan is gone! The jailer opens the cell and takes a quick look around. Not seeing Susan, he runs off in search of her, leaving the door unlocked. However, before Susan can get very far out of the cell, Lemaitre returns, call for the jailer, and captures her. She is returned to her cell and Lemaitre brushes off the jailer's protestations. He would rather talk to the Doctor.

The Doctor resorts to bluster, insisting that Susan be released, but Lemaitre tells him he is in no position to insist on anything. The Doctor asks if Lemaitre knows who he is talking to. Lemaitre assures him that he will soon know. He shows the Doctor his ring and his old clothes. The Doctor denies they are his, but Lemaitre presses for the truth. He says he knew about the Doctor all along, tipped off by the tailor. The Doctor asks why he was not arrested before, instead Lemaitre played along. Lemaitre explains that he needed people he could call on for favors, even if they were enemies. He kept the Doctor at the prison in case he was needed. The Doctor asks why he was allowed to move freely today, and Lemaitre explains that it was because Barbara and Susan were held prisoner. The Doctor could be counted on not to leave. Realizing that Lemaitre knows all about himself and his companions, and knowing that Susan is under Lemaitre's control, the Doctor has no choice but to help him find Jules Renan's house.

At the house, Barbara comes back downstairs much calmer. She is looking to apologize to Jules for her earlier outburst but finds only Ian. Jules is out looking for the Doctor and Susan. Ian assures her that Leon's death was unavoidable, and while she understands this, she also says that she is sick of all the death they seem to encounter. They can't seem to get away from it. Jules returns shortly with no news, but he has left the front door unlatched. Now they must face the hardest part - waiting. Barbara begins to apologize, but Jules already understands. He too admires Leon no less for finding out he was on the other side. The sides in the conflict are quite nebulous. He himself is not an aristocrat, as Ian assumed, but someone caught in the middle who chose the side he felt right. He is simply fighting to see that anarchy does not rule France. But there are really only two sides.

Ian fears that Lemaitre has brought soldiers to arrest them all, but he insists that he came alone and unarmed. The Doctor tells them that he was forced to bring him as he holds Susan prisoner. Lemaitre explains that he was the one who helped Ian escape from the prison, arranging to get him the key and incapacitating the jailer. He did it because he knew that Webster had talked to Ian. Now he cannot wait any longer and must get the message. Lemaitre reveals that he is James Stirling, to great disbelief. There is disbelief all around, but it does make sense as Stirling had to be someone in authority. Who better than Lemaitre. Jules is upset that Stirling hadn't confided in him, but Stirling says that Jules' group was unknown to him when he arrived and he did not know whether Jules could be trusted.

The Doctor has had enough of this and demands Susan's release as he has kept his side of the bargain. But Stirling insists that Susan is perfectly safe where she is and says that he must tell his story first The Doctor reluctantly agrees. Stirling wants to start by getting Ian's message as he knows it is urgent. He had been expecting a message from England at any time. Ian relays Webster's simple message: Stirling is to return to England immediately. But Stirling is convinced that there was more and presses Ian. Ian cannot remember. Stirling says that he was already planning to return to England right after he completed one last task for Robespierre - following Paul Barrass to his meeting this evening and learning the plan to overthrow the First Deputy.

This comment triggers Ian's memory and he says Webster did say something incoherent about "Barrass, meeting, and 'The Sinking Ship'." Jules recognizes this as an inn on the Calais road and all agree that this is where the meeting will take place. Now they know, they can go ahead of time and observe. Then the Doctor and his friends can be taken safely out of Paris. Stirling suggests that Ian and Barbara go to the meeting as Barrass will surely recognize him. The Doctor attempts to protest, but the matter is decided. Jules will go with them to show them the way. He gets a map and shows them the route.

Later that evening, as a storm begins to roll in, Ian and Barbara pose as innkeepers at 'The Sinking Ship'. Jules sits at one table posing as a customer, and there are two other legitimate customers at a far table. It is getting late, and Barbara worries that Barrass will not show up. She goes into the back room and finds Ian finishing work on a peephole in the back of a bookshelf.

Shortly, Barrass arrives. He asks after Jacques, the innkeeper, and Ian says he has fallen ill and asked him to take over. (In reality, Jules has bound and gagged him in the cellar.) Barrass is shown to the back room and orders a bottle of wine for two. After Barbara serves Barrass, the other customers leave, as does Jules. It is up to Ian and Barbara now. Soon, Barrass' guest arrives - a short man in a duffle coat and a muffler obscuring his face. Barrass greets him and shows him to the back room.

As Ian and Barbara watch, the man reveals himself. It is Napoleon Bonaparte! Barrass explains that Robespierre will be arrested tomorrow at the assembly, tried and executed. But Napoleon is coolly sceptical. Robespierre is influential and has a talent for bringing people to his side. Barass assures him that this will not happen, but even so, Napoleon wonders what this has to do with him. A new governing committee will be formed, and Barrass will be part of it. The constitution could then be rewritten anyway they saw fit. He flatters Napoleon and says he understands the general's dislike for politicans who fight among themselves while France's enemies wait to pounce. He says that France needs a strong leader who has the support of its people, to manage affairs both internally and externally. Napoleon is that strong leader.

Napoleon hears all of this but is still sceptical, especially when Barrass proposes a government run by three consuls, of which Napoleon would be one. He fears he will be only a figurehead. Barrass assures him that this will not be the case, and the glint in Napoleon's eye shows that he will make certain it is not the case. Napoleon agrees, but only if the overthrow of Robespierre is successful. Otherwise, he will deny this meeting took place. Barrass will summon him to Paris as soon as all the preparations are completed.

Back at Jules house the next day, Stirling receives the news with shock and surprise. He knows that Napoleon will not be content to be one of three equal rulers. He will stop at nothing to rule France. The Doctor interrupts his thoughts and says that Susan is their only concern now. Stirling is worried, though, that if Robespierre is arrested, he will be taken to the Conciergerie Prison and it will be too hard for Susan to get out. When Jules says that the assembly meeting should be nearly over, they know they must act fast. Barbara, curious, asks if Jules would actually want to keep Robespierre as ruler of France, and he says that he would take anyone over Napoleon. At least Robespierre is not a dictator. She protests that Napoleon's rise is inevitable, but the Doctor stops her and repeats the urgency to free Susan. Stirling will take Barbara to the prison and wait outside for the rest, the Doctor will go to the prison to get Susan, and Ian and Jules will go to Robespierre's office to find out what has happened to him.

As the others leave, Barbara seems amused. She explains to the Doctor that this feverish activity to halt the inevitable amuses her. Robespierre will be caught and guillotined no matter what they do. But she knows that they cannot alter history - she learned that lesson with the Aztecs. The Doctor agrees that they can't stem the tide of history, but they can keep themselves from being carried off with the flood! They hurry to the prison.

Meanwhile, Robespierre hurries into his office and locks the door. He looks scared and desperate. He grabs a pistol from his desk drawer as a mob of citizens and soldiers shows up outside the office. Preparing himself, he faces the mob as it breaks in to arrest him. He begins to talk, trying to win the citizens to his side, predicting that they will not succeed. Within hours he will be as powerful as ever and will save France. As he speaks, Ian and Jules arrive outside the office. They can't see him, but they hear as Robespierre's words are cut off by a gunshot. Shortly, the former First Deputy is dragged out, holding a hand to his face. He has been shot in the jaw. Ian tells Jules that Robespierre is finished and that he will be taken to the Conciergerie Prison. Their fate is in the hands of the Doctor now. He must get Susan out in time.

At the prison, the Doctor and Barbara have found a place to conceal themselves outside. The storm is getting ready to break and will further hide their movements. The Doctor heads inside to find the jailer and his guards having a grand party, drinking heavily. The jailer is angry, insisting that he has a score to settle with the Doctor. The Doctor asks if the jailer has heard the news of Robespierre's downfall. He has. The Doctor adds that Lemaitre was shot trying to escape and that he will now deal with Lemaitre's accomplices, including the jailer. The Doctor explains that he was part of the plan to overthrow Robespierre all along, his high office is the proof. The Doctor orders the guards to hold the jailer for carrying out Lemaitre's and for betraying him to Lemaitre.

The jailer protests his innocence and/or ignorance and the Doctor quickly turns this to his advantage. He "releases" the jailer and sends the guards away. He graciously allows the jailer to retain his post - temporarily - while the new government takes shape. The jailer is grateful. The Doctor tells him that Robespierre will shortly be brought to the prison and that his friends will be rounded up by tomorrow. Soon the jail will be full. The jailer offers to release all the current prisoners to make space for the new ones. The Doctor takes the key for Susan's cell and the jailer heads off to release everyone else.

Outside, Barbara watches as the mob bears Robespierre into the prison. Ian and Stirling arrive shortly afterward and meet up with her. They await only Jules and the Doctor with Susan. Stirling says that he will head to Calais and there board a boat for England. Ian offers that they all travel together part of the way, as that is the same direction they are heading. Shortly, Jules arrives.

Inside the prison, the Doctor releases Susan. As they head out, the hear the sounds of the mob and Robespierre is brought in. The jailer is quick to mock him, and all the citizens cheer. As he is hauled off, the Doctor muses on the quirks of fate that time can play. Yesterday, everyone lived in fear of that man. Today it is completely different. They leave the prison. Jules tells his friends that the fall of Robespierre has changed everything for him. First, he will find Jean, then he will hide out to see how the political situation settles out. He wonders who will be the next ruler of France. Ian suggests he remember the name Napoleon. Nearby, Stirling is sceptical when Barbara tells him their destination and he suggests instead that they accompany him to England. When Barbara tells him they must travel in their own way, Stirling asks who they are and where they come from. Barbara is saved from answering when the Doctor and Susan arrive and the reunion is complete. The TARDIS crew head for the carriage while Jules and Stirling speculate as to who they really are and where they are going. Jules says that he's not sure they know where they are heading. Come to that, do any of us?