A UNIT corporal walks through the woods with his eyes wide and glazed over, his movements jerky and stilted.

The TARDIS appears and Sarah and the Doctor emerge -- he in a lighter coloured jacket of grey with brown patches and cuffs and a darker floppy hat. Sarah is offered ginger pop from the Doctor but she can't stand the stuff. The coordinates were set for Sarah's time but the linear calculators are off. The TARDIS is due for a 500 year service. It smells like a rain has just happened but the ground is dry... there hasn't been any rain here for a week. The Doctor pulls a device and finds out there is an enormous wave of energy. He tells Sarah they are on Earth since acorns and oak trees do not grow anywhere else in the galaxy. The Doctor does an innie-minnie-minie-moe and points in a direction over his shoulder. As they walk, he warns her to watch the bramble but she gets hit with it. She asks him what is so special as innie minnie minie moe and he tells her it is as good as fee fi foe fum. They do not see the UNIT corporal walking through the woodland. They stop as some men in white suits and helmets approach. Sarah is wary but the Doctor tries to talk to them... and is shot at by the foursome... who have guns in their pointer fingers. Sarah and the Doctor run.

The Doctor is going on and on about something or other and mentions the Duke of Marlborough. Sarah ploughs past him, "Oh come on, Doctor, let's get out of here!" She falls down a hillside, screaming. She clings to the side of a cliff. Despite the Doctor telling her not to look down, she does. He pulls her up. They see the UNIT man stumbling. They yell to him to stop but he runs right off the cliffside and ends up dead in a quarry. The pair climb down to him and find all new specially minted coins, no scratches, all dated the same year. They also find a strange stone like object which the Doctor thinks he has seen before, "My memory's getting terrible. You know 300 years ago, I would have recognized this like a shot." There is a shot. Two white suited humanoids are standing on the hill and firing their fingers. After ducking down behind the object, the Doctor and Sarah flee and are followed. They pass a park bench and avoid the white suits.

The Doctor and Sarah arrive at the foot of a town, a town Sarah recalls. Two years ago she came here on a story: Devesham, an English village. It is very quiet and there is no one about. They sit on stone steps to a large podium, a Market Cross. Seeing no one, they rush to the pub, the Fleur-de-Lys.

Inside, it is just as quiet and empty. Behind the bar, the Doctor calls it the Marie Celeste and finds inside the cash register more freshly minted money all the same year. The Space Defense Station was here and there was a bru-hu-ha over it two years ago which is why Sarah came here then. The Doctor thinks it might be radiation sickness...the soldier might have been affected by it and the village evacuated. A dangerous substance leak. Sarah thinks they have been walking around in the middle of it like a couple of narners. Sarah calls him over to the window. The soldier is alive and with four of the white suited figures. Sarah, watching, bangs into a glass and it falls. The five move toward the pub door but a lorry arrives with villagers on it: people of all types. Trance-like, they come off it and fill up the town. Mr. Morgan is the man in the checked jacket. Sarah and the Doctor hide in the storage room and peer out as the people come into the pub and occupy it. One clears his throat. For unearthly moments the people just stand or sit quietly. The clock strikes on the hour of 8 AM and the people begin to move about like normal.

The Doctor and Sarah talk about this. He wants to find the Space Defense Station and contact UNIT from there. He tells Sarah to stay here and keep an eye on things: she will be all right here. "I've heard that before," she says. But she also tells him she can find her way back to the TARDIS all right. He gives her the key from his pocket. If anything goes wrong, he is to meet her there. The "dead" corporal finds her and opens the door. She tries to act normal and talks to Mr. Morgan. No one talks until she asks for somebody to say something. The corporal grills Sarah and asks about strangers. Morgan thinks she might be part of the test and tells her to go. She offers to help if there is some kind of trouble but backs away when they won't respond. Backing to the door, she snaps something about the Corporal breaking his neck earlier.

Outside, she hides behind the lorry as a man in a white suit turns around, his helmet up to reveal a face of machinery...he's an android. Sarah runs off and he notices.

The Doctor enters the sliding doors of the Space Defense Station and asks a soldier if he can help him. The man doesn't respond. "I tell you what, I won't bother you," the Doctor states and begins looking into offices for the Commanding Officer.

Sarah runs to the TARDIS, puts the key in the lock, and moves away to examine the strange coffin device. The TARDIS leaves. Sarah calls, "Doctor, don't go, I'm still here." As she watches the empty space where it stood, a hand comes out of the slightly opening coffin. A man is lying in it. She bends closer to see if she can help him but he grabs her, meaning to choke her.

Commander Guy Crayford, a man wearing a patch over his left eye, is called by a craggy sounding voice belonging to Styggron. Styggron orders all units to discharge stations -- a unit may have gone random. Crayford moves to find out but hides in a room the Doctor almost checks. The Doctor checks the Brigadier's office, "Alistair?" He enters and finds some papers on desk. And a map. From the adjoining office, Crayford comes in and points a gun at him, "Keep your hands where I can see them." The Doctor mentions those are the first friendly words he's heard since coming to this town. Crayford asks him what he is doing. "Oh just dropping in, I do from time to time." The Doctor has his hands up with the map he was looking at spread between his them. Crayford grabs it down from him. The Doctor tells Guy that he is the Brigadier's unpaid scientific advisor. Guy has heard of the Doctor. His arms are beginning to ache. The Brig is in Geneva and Colonel Faraday is in command. Guy wants to put the Doctor in detention. The Doctor stalls and grabs the desk and flips it. This gives him the chance to run out. Crayford shoots his pistol at the Doctor and orders men after him.

Alarms ring out. The Doctor climbs up a ladder to the roof, followed by a soldier. A soldier on the ground fires at him, joined by another. The one who followed fires a machine gun at him. Sarah watches from a corner, hidden, as the Doctor jumps off the roof to land on his feet. Two men in white surround the Doctor. "Is that finger loaded?"

Sarah gets the locks open and the Doctor out, then she follows him.

Crayford, on a screen, explains to Styggron about the Doctor and Sarah. Suddenly alarms go off. Soldiers rush around.

In a small storage space, Sarah and the Doctor confer. Sarah tells the Doctor that Crayford was lost in deep space on the first test of the XK5 space freighter two years ago. It was thought an asteroid destroyed his ship, "Guy Crayford is dead, Doctor."

Crayford informs Styggron that the guards have been given orders to shoot to kill. Styggron doesn't want that. He wants to learn what the Doctor has learned of their plans.

Sarah and the Doctor emerge and open a wooden door when they see Sergeant Benton. "It's a small world," the Doctor says. When Sarah happily and playfully sneaks up on and introduces herself to Benton, Benton pulls a pistol on them.

Styggron makes Crayford's mind burn with pain until Crayford announces that the order to kill is cancelled. This gives the Doctor and Sarah time to get away from the indecisive and stunned Benton. Benton alerts other guards from B Block.

Sarah and the Doctor are behind a desk. They duck as Crayford and Harry Sullivan pass by, Harry taking orders from Crayford. Sarah is not sure of what is going on. The Doctor doesn't think Crayford died but that something came back with him on that ship: something that is controlling human beings for miles around. He wants to get back to the village to warn London. The pair get out and into the woods. "So far so good," the Doctor comments. "As the man said when he fell from the skyscraper," Sarah jokes. They hear dogs which are may be used to track them. As they continue to run through the forest, Sarah falls and sprains her ankle. Yet they continue on, the Doctor checking to see if she is all right.

Soldiers are using the dogs to track them.

Sarah cannot keep going on. She won't let the Doctor carry her. He carries her to a tree to hide her in and takes her white scarf to draw the dogs off. He tells her to try to see him at the pub. If he is not there in an hour, he tells her to meet him at the TARDIS. As he runs out of earshot, she tells him about the TARDIS being gone...but he cannot hear her. As he runs, the Doctor drops his hat and jacket as well as Sarah's scarf and soon his own scarf to lure the dogs off. The dogs find his shoes. The men think the Doctor must have swum across a lake. After they start to move off, the Doctor emerges from the lake.

Sarah is down from the tree but the men and dogs are trying to move around the lake and see her.

Styggron has other plans for the Doctor, so he does not want him seized. In a rocky interior area, soldiers bring in a downed, unconscious Sarah Jane.

Back in the village, the Doctor tries the village call box phone but it doesn't work.

Sarah is shackled to a metallic table and when she awakes, Harry says, "It's no good, Miss Smith," to stop her from struggling. Harry uses a device to start the analysis of her brain. Sarah is hit by blue lights and a strange alien face that looks like rock is in her vision... barely.

In the pub, the Doctor does not find a working phone. He opens a door and finds Morgan just standing behind the storage room door which he opens. Morgan claims the phones are down due to a gale storm. The Doctor smiles, "I always told Alexander Bell that wires were unreliable." When Morgan asks what the Doctor wants to order, the Doctor asks for a pint of ginger beer. The Doctor doesn't give much answers to a questioning Morgan. Not much happens here except the Dart's Night. The Doctor throws the darts and then finds the dart board is new, never been used before. He looks at it. Watching on the other side is Styggron, a scientist who wants his techniques to be flawless in his people's conquest. His people are the Kraal. With him, disagreeing, is another Kraal -- Marshall Chedaki. Chedaki thinks the time to experiment is over but Styggron believes there are other worlds they can conquer. They have made their experiments for Earth complete. Chedaki explains that the knowledge from the girl's brain has given them the knowledge that the Doctor is a known challenger of conquests and has allied himself with libertarine causes. He thinks the Doctor should end, something Styggron assures him will happen. Styggron orders Crayford to commence with the final test.

Crayford tells Harry to make sure the girl is properly guarded. Harry tells him they have taken care of that and that from her they have her memory prints and body parameters which are being coded. Styggron wants to run a test on the Doctor.

The Doctor is looking through his magnifying glass (which he puts back in his jacket pocket) as the coasters on the bar and also sees plastic horse brass hanging on the walls. Morgan watches him intensely. The Doctor tries to get rid of him and orders another pint of ginger pop. He leaves money on the counter. He also finds the calendar on the wall has the same date on every page -- July 6, "Strange. A village without a future." The phone rings and it is Sarah for the Doctor. She claims she managed to escape. She tells him she knows the aliens' whole plan now. The Inn, one of their centers, is not safe for them to talk or meet so she tells him to meet her at the Village Store. He can cut through to it behind the pub. She warns him about the robots.

"Don't worry, Sarah, who'd notice me?" He hangs up with her to leave to meet her and finds the phone not working again before he leaves, "Thanks for the hospitality."

Chedaki fears the androids could be used by the Doctor to attack them. The androids, he claims are indestructible and unstoppable. As he leaves, Crayford reports to Styggron. Styggron tells Crayford he must be reprocessed. Crayford does not think he can go through that again. His experience will be put into a new android, one programmed to attack Kraal.

The Doctor runs through the village behind the pub to the AV and NG Kirby store. Sarah is hiding behind a counter. She explains that she was knocked out and captured by the soldiers. He gives her some ginger pop to drink that he has in his pocket. She drinks it. Sarah tells him that the Harry there in the Space Defense Station is not the real Harry. They are copying people. The Doctor looks out the window and sees two white robots arrive. The Doctor wonders how Sarah made the phone call...he deduces they are being tested...that Sarah was allowed to make that call. He looks out again and sees the robots leave. He thinks that the aliens sent the robots through a space time warp to Earth. He wonders what the aliens are afraid of. If they have that much power...he will take her back to the TARDIS where there is a radio.

With Crayford's memory cells, Styggron plans to make a totally hostile android. He puts Crayford through a disorientation chamber and from this creates a soldier, a total killer android. He activates the hostility circuits. Styggron has to use his ray gun on it, destroying it. It vanishes into metallic parts and then nothingness. This shows Chedaki that the android could be done away with. His gun weapon is a new one but he has his science unit working on more. Science will make them invincible.

The Doctor runs off. The faceless Sarah sits up and fires the pistol at him.

Chedaki fears the Doctor being at large, "He is a Time Lord." Both the village and the Doctor will be destroyed in nine minutes using a matter dissolving bomb. Sarah overhears Chedaki and Styggron talking about this. The virus which the androids will use to cleanse the Earth needs to be tested on a live human organism: Sarah! When the two and a guard Kraal leave, Sarah gets up and groggily sneaks out.

From a bush in the village, the Doctor spies on a truck and the white suited robots as well as the human looking androids. They all drive away on it. He moves across the square near the pillar.

Androids go into the strange teeth like door of the Kraal base and the doors will be secured. Sarah sneaks out with about four minutes left.

Outside, the Kraal grabs the Doctor from behind, "Resistance is inadvisable." He tosses him to the pillar and white suited robots use vines made of metal to tie him to it. The Kraal sets an M-D bomb to vaporize the simulated Earth. Sarah comes calling and the Doctor calls her to him but she doesn't notice he's tied up. He tells her to use his knife in his right hand pocket. It is artificial ivy. He instructs her to use the sonic screwdriver, set on Theta Omega. With 20 seconds, the Doctor runs, leaving her. She knows the way out. So does he seems as he leads her and prompts her to an opening in the bushes which is the entrance/exit to the Kraal complex. They just make it in as the countdown ends and the vaporization of the town leaves a desolate, desert planet, barren in its landscape.

Inside, they barely recover when UNIT androids lead by Harry and the human Crayford surround them.

Time to lift off is 90 minutes and androids are being loaded now. Crayford reports to Styggron, who orders him to have the Doctor and Sarah killed. Crayford questions this now. He thinks the knowledge of a Time Lord will be a valuable addition to the data banks. Styggron calls him puny like all his race. After Crayford leaves, Styggron tells another Kraal that they shall analyze his brain, then he shall die.

In a low ceiling cell, the Doctor and Sarah talk about what is going on. Sarah realizes this is not Earth and it all makes sense to her now. "If I had had my wits around me, I would have known it from the start." The only planet with levels of radiation as high as they picked up when they left the TARDIS would be Oseidon, the Kraal's planet. The sonic screwdriver cannot open the door as the Doctor was trying. Radiation will make them ill after a long time... any level is too high and it is getting worse all the time and the planet will be uninhabitable before long. The village and the woods and all were like a training ground.

Crayford was listening at a wall tube to their conversation. He enters with a guard and admits this. "Well, nobody's perfect," the Doctor said and tells him that his plans are doomed to fail in the end. The Doctor tries to present a flaw in his plans. Projected through the space time warp, back to Earth, the plan will have Earth convinced that Crayford rationed his provisions using his water recycling experiments. Crayford has already made radio contact with Earth. He told them a stabilizer failure left him into orbit around Jupiter. Sarah asks him why he is betraying Earth. He tells her Earth betrayed him and he defends the Kraals, who saved him. He was dying, being torn apart by gyro failure. He was reconstructed except for the one eye, the left one that could not be found. Crayford wonders why the Kraals with such knowledge and skill, should be left to die. The Kraals told Crayford they are just going to take over the Northern Hemisphere. They promised no humans would be harmed if they accept the ultimatium. The Doctor tells him he's been brainwashed. The shells of the android coffins will be mistaken for meteors as they enter Earth's atmosphere. The Doctor asks why Styggron tried to kill him. As Crayford explains, the Doctor goes on talking to himself about this, murmuring. Crayford doesn't seem to notice but he keeps on talking, too.

Styggron's machine feeds into a computer the memory and intelligence of any living being...it is painful but better than dying. Crayford tells them to trust him. He leaves. Sarah tells the Doctor about the TARDIS being gone.

Styggron makes Harry's android put one drop of the virus culture that will kill the entire human race into a jug of water that will be given to Sarah and the Doctor. Harry puts the main virus in a sterilizer rock like container. Harry takes the tray to the detention cell.

Before he arrives, the Doctor removed a floor plate and found a group of wiring to give a guard a good stiff jolt. They will randomize him. Harry comes in and they cover the plate to hide their sabotage. Harry gives them the food and drink...bread and water. Sarah starts to take a drink as Harry takes the Doctor out...roughly. He calls to her and tells her to remember -- water is an excellent conductor. Rather than drinking it, she pours it back into the jar.

The Doctor is brought to the lab. He tries to jump past Harry and the UNIT androids but they all grab him and put him onto a scientific table. Sarah disconnects a wire junction.

Styggron explains what will happen to the Doctor. He also tells him that Earth will be destroyed -- it cannot be wasted on human beings. He explains about the virus and contagion: the Earth will be rid of humans in three weeks and the virus will burn itself out. Styggron will remain in Crayford's rocket and then signal Marshall Chedaki's fleet to land. The Doctor comments, "The best laid schemes of mice and Kraal's..." The lights pass over the Doctor's body and he begins to feel the pain...

While this happens, Sarah sets up her ruse: the wire end is at side of the door and she has put water across the entrance. She takes off her scarf and burns the end to create smoke. The guard comes in and Sarah points the tube as his gun. This makes him short circuit and he gets a hole blasted in his computerized chest. He falls and Sarah sneaks out, hitting her head a bit.

Styggron will leave the Doctor to his death. The Doctor's brain tissue will expand under the stimulation until his skull bursts -- the machine will be left on. Styggron thinks the Doctor will soon be screaming for mercy. Sarah hides as Styggron passes. She finds the lab and the Doctor. Working the device, she turns it lower but another switch makes him feel worse. Finally, she gets the horrid device off and unchains him. He talks gibberish, "Once upon a time there were three sisters and they lived in the bottom of a treacleware and their names were Olga, Marsha, and Erena, are listening, Tilly..." The pair move out for Crayford's ship. It will be leaving in a moment.

The Kraals find that the Earth female has escaped.

Sarah passes out but is awakened a short time later by the Doctor. The G-force cut the blood supply to what the humans call their higher senses. A copy Doctor, an android peeks out of a pod. The Doctor mentions that what they just went through was a gentle massage to what's ahead. She doesn't want to know but he tells her: they will have to travel to Earth in the pods. The Doctor wonders about the retro tubes and the impact: will the tubes firing be enough to keep them alive through the impact? Sarah sums it up: "So providing we don't burn up on re-entry, and aren't suffocated on the way down, we'll probably be smashed to a pulp when we land."

The Doctor tells her it is the one thing, the one tiny flaw in their plan. She reminds him it is just his plan. They are beamed through the space time warp now.

At Earth's Space Defense Station, a black girl, Tessa, picks up Crayford's ship. The man in the scanner room, Grierson, calls Colonel Faraday. Benton comes into the entrance way and tells Harry there are no signs of the Doctor or Miss Smith. Harry brands Benton a pessimist, "What could possibly happen to the Doctor in Devesham woods." Benton tells him that he's never known the Doctor to leave the key in the TARDIS door before. Faraday meets them and they join him to the control room.

Thinking this a historic moment, Faraday tells Grierson that Crayford has been further into space than any other human being. Harry gives Benton a knowing look: Faraday is wrong, the Doctor has taken plenty of other human beings further. Faraday calls Crayford, "Welcome home." They lose Crayford's call when Crayford explains he's had some problems. Grierson picks up some fireballs...meteorites. Matthews tells them that Crayford will be back in time for a late breakfast. Grierson wonders why meteorites are slowing down. Even Benton knows meteorites should burn up before they hit the Earth. The pods land in an open field.

A pod opens and the Doctor comes out of it. There is no Sarah he finds or rather doesn't find.

Crayford calls control again and they lock on to his ship. Matthews does a countdown. Sullivan stands by to do a medical. Crayford asks if they have champagne on ice.

Sarah stumbles out of the woods to find the TARDIS. She opens the door slightly but shuts it again. A pod is near the TARDIS. The Doctor taps her on the shoulder -- he had to be sure it was her. He says there is a replica of Sarah around somewhere. This Doctor is not the real Doctor. The pod opens and an android Sarah sits up. The android Doctor reaches out to get her but she runs off. The android Doctor helps the android Sarah out of her pod and beckons her to come, "We have much to do."

After some slight drift, Crayford lands and docks. Faraday takes Harry to go aboard. Styggron is with Crayford.

The Doctor enters Space Defense and shows the "dead" soldier his pass. The Doctor asks if this is the first time he has seen him today. He wants to be notified if the soldier sees him a second time today. The man thinks the Doctor mad but the Doctor moves toward the scanner room.

In the control room, Benton is on the phone with his kid sister whom he is taking to a dance at the Tully tonight. The Doctor marches in and Benton asks questions. The Doctor tells Grierson to call Harry back down. The Doctor takes the mike and tells him not to go into that rocket. Harry tells Faraday to do as the Doctor says. Faraday wants a good explanation. Harry and Faraday are to come back down on the lift. Grierson notes the lift is coming down. The Doctor does some figuring while a Matthews android hits the "dead" soldier. There is also an android Benton with him. The real Benton is on the floor unconscious or dead. The soldier falls on top of him, unconscious.

The Doctor has given Grierson some figures that will build a special circuit into the radar dish. The Doctor tells him to recheck the eleven circuits he must to do it and to tell no one what he is up to. Faraday comes in with Harry. The Doctor explains some about this invasion. "Kraals, I've never heard of them," Faraday says. They go to Faraday's office where Faraday will authorize Harry to do medical checks on everyone. The Doctor tells them there are android replicas of Faraday and Harry. "The confounded cheek." The Doctor tells them he has a detector that lights up in the presense of androids. It lights up. The android Doctor shows up outside the door and the real Doctor has to dive out through the glass window as Faraday and Harry with him are also androids. Recovering, the Doctor hears Sarah calling to him from a corner of the building.

As he runs to join her, the android Doctor shoots a pistol at him. Faraday makes an announcement: the Doctor has been trying to sabotage their defense system. He gives all personnel authority to shoot on sight. The two figure Faraday and Harry must be in the rocket with Styggron. The Doctor makes her stay at a building corner and he goes into the entranceway. Benton pulls a gun but the Doctor feigns that he is the android. "Keep your wits about you. Nobody knows who's who around here."

Sarah starts to climb up the rocket to help Harry and Faraday.

Another Doctor comes into the entranceway. Benton fires his gun into this Doctor and it has no effect. This is the android Doctor, who goes to the scanner room and shoots Grierson just as the man is about to switch on the radar jamming unit. Crayford arrives and tells the android Doctor not to kill the Doctor. The android also tells him about the virus. Crayford tells them that Styggron wouldn't do that. The real Doctor explains to Crayford that he has been brainwashed: nothing went wrong with his ship -- the Kraals hijacked his rocket and there is nothing wrong with his left eye. In front of a mirror, Crayford removes the patch: his left eye is just fine. Crayford moves out and the android Doctor is distracted. The real Doctor hits the gun and one of them is knocked down. One of them hits an alarm.

Harry and Benton androids rush toward the scanner room. The real Doctor recovers and hits his head on the console. He makes his way toward Grierson's control to activate the jamming. The two Doctors fight with the android stronger and getting the upper hand. The Doctor manages to hit the switch which stops the androids into slow motion and then still. The android Doctor was about to bean the Doctor on the head with a chair.

In the rocket, Sarah finds Harry and Faraday tied up. She unties them.

The Doctor asks a wounded Grierson if he is all right. Grierson was hit in the left shoulder with the bullet. He tells the Doctor that Crayford went back to the rocket.

Styggron enters the area where Sarah, Faraday, and Harry are, "The enterprizing Earth girl." He has a ray gun on them. The sensors detected an intruder. He calls her life "charmed" and reveals the water had the virus in it. Styggron has the vial with the virus. Crayford appears and attacks Styggron, who admits he used him. They fight but Styggron shoots Crayford down. The Doctor appears and fights Styggron. Styggron falls onto the virus and dies but before he does, he gets off a shot with the ray gun and the Doctor is hit. The Doctor falls, seemingly dead. Sarah rushes over to the Doctor's body, "Oh no!" The real Doctor appears. He reprogrammed the android Doctor to confuse Styggron. "Please, don't ever do anything like that again."