Edinburgh 1773. Katherine Monro is sitting by the fire, sewing. Her husband, whom she has not seen for two days since he left for his estate to indulge his new interest in gardening, bursts in carrying a child. He says he found it abandoned and presents it to her. He says that they will keep it and call it Alexander.
A stagecoach is racing out of control through the streets of Edi nburgh, its horses galloping blindly while the driver tries futilely to rein them in. It is 1759. The Doctor is surfing on top of the carriage, trying to distract another man who is attempting to attack the driver. The attacker is a pale man with black marble eyes. Four soldiers in red jackets run down from the castle and fire a volley of shots at the stagecoach. The attacker turns his attention to the Doctor, or possibly the roof of the carriage. The crowds in the street scream in panic and crush to the sides of the road for safety. Five minutes earlier the Doctor and Martha were sightseeing on the ramparts of the castle. Now Martha is running at full sped through the busy streets to get in front of the stagecoach. Just as it seems she is about to be run down she uses the Doctor’s sonic screwdriver on setting three four seven as he told her. At the same moment the pale man on the roof of the stagecoach is hit by a gunshot she is pulled to safety. The horses slow down and the carriage slews around and comes to a halt. As the pale man falls from the roof, the Doctor rolls with him and lands first on the cobbled street where they are still lying when Martha arrives.
After checking that the Doctor is alright Martha turns her attention to the pale figure beside him. Not only is he dead but he has been for some time. He has an autopsy scar on h is back. Using his sonic screwdriver the Doctor ascertains that the man has been dead for two days from a brain hemorrhage. The four soldiers arrive and surround them. Meanwhile their captain, McAllister orders the stagecoach to be on its way and arrests the Doctor and Martha for ambushing the stagecoach. Despite the Doctor’s psychic paper, and their protests that they were trying to stop the pale man’s attack on the stagecoach, they remain under arrest and are taken by the quartet of soldiers to the Tolbooth. As they are marched back up through the city it becomes clear that the Doctor recognized a passenger in the coach as being Benjamin Franklin, not only a great inventor but the Pennsylvania Assembly’s agent to the British Government.
The Tolbooth is a four storey building where the council meets. It is also furnished with prisons. As McAllister heads off to the Lord Provost he orders his men to put the prisoners in the cells but the Doctor grabs Martha’s hand and sprints off up towards the castle. This takes the soldiers by surprise and they take a moment before they give chase. When they finally catch up it is because the Doctor has stopped in the middle of the large open space that stands before the castle. He holds out his psychic paper again. It says that he is the Baronet of Nova Scotia. He tells Martha and the men that the exact spot he is standing on was made into a part20of Nova Scotia so that there was no need to sail to Canada every time a new Baronet was inaugurated. While one of the soldiers agrees that this is true a second goes to fetch Captain McAllister and a third says it would be best to shoot them. As the two remaining soldiers point their guns at him the Doctor takes out his screwdriver. Martha expects him to switch it on but instead he uses it to flick one of the soldiers between the eyes, causing him to drop his musket. The Doctor stamps on the other man’s toes with the same result. Then, gathering up the guns, the Doctor and Martha run again.
The Doctor acts as a diversion by running down the hill towards the soldiers while Martha goes to examine the corpse of the man that came back to life. To do this she has to climb into a cart, under a tarpaulin but finds herself being taken away with the body. The cart stops in the courtyard of a large building and Martha is discovered by a soldier. Standing nearby are two men in dark robes. They are similar enough to be father and son. The soldier tells them that there was an incident on Cowgate and that Martha was involved. She interrupts to say that the corpse was involved: he had something sewn to his chest but it fell off in the incident. This prompts the younger ma, Mr. Monro, to tell the soldier that Martha is their servant, an orphan who was placed into their care due to her ‘troubles’. The two Monros take her into the Surgeon’s Hall. There they start to bicker. The elder is perplexed that they have taken Martha, but the younger says that she is a witness, and that their work is nearly complete, so keeping her for a few hours will be no problem. Martha tells them that she knows they have been sewing something to corpses in order to reanimate them. The younger Monro says that he will show her what they have been sewing on. He pushes her into a dark room and locks the door behind her. There is the scuttling of many creatures around her. Martha uses a match to light a lamp on the wall and sees that the room is filled with dozens, hundreds, of dismembered hands.
The Doctor races down the grassy slope of Castle Hill pursued by a party of Redcoats. One of the soldiers stops to fire his musket. The shot ricochets off a rock and hits the soldier closest to the Doctor. This man falls, tumbling down the slope towards the Nor’ Loch. The Doctor dives across to bring him to a halt. He is soon surrounded by ten soldiers. McAllister orders the Doctor to be taken away for trial and execution when his gaze is attracted by the sight of the Nor’ Loch, where dozens of weed-strewn corpses are emerging from the water.
The corpses appear to date from the fifteenth century to more contemporary deaths. They are glassy-eyed but well preserved. McAllister declares that the city is under attack. Despite the Doctor’s contradictions the soldiers open fire on the corpses. Despite being hit by this barrage the corpses continue to emerge unimpeded. In fact, they suddenly become hostile, lurching towards the soldiers with hands outstretched, fingernails of steel ready to rip out their throats. As it is apparent that the soldiers are about to be over-run the Doctor orders the retreat. McAllister is furious but has to pretend that he issued the order so as not to lose face with his men. They flee up the hill back towards the castle but it becomes apparent to the Doctor that the corpses will cut them off. He tells McAllister to order his men to turn back and run down to the Loch. McAllister argues that there may be smugglers down there who will open fire but the Doctor persuades him that a smuggler’s boat will give them an escape route. The soldiers turn back. However, the last one is caught and killed, quickly joining the gang of corpses in their downhill pursuit. On the shore they find a raft and quickly paddle into the middle of the Loch as pale hands break the surface to grab at them. On the far shore a minister urges them on and leads them in a desperate race to the church of St. Cuthbert where the large oak doors are locked behind them just as the corpses arrive.
In the dark room Martha sees that the many hands have lost interest in her and are more intent on reaching the dim light from the window. She notices from the pattern of scars on their fingertips that each is identical to the others. A tap on the door announces the elder Monro who has come to release her. He uses a battery made of an earthenware pot and copper wires to paralyse two hands which he puts into a sack. Another hand leaps for his heart but Martha uses the battery to save him before they escape through the door. Monro is astonished. He tells her that he sewed a hand to Arthur King’s body to take control of him and now another hand has tried to do the same to him even though the two hands had never been in contact. Somehow the disembodied hands can learn. He tells her that the hand had caused King to come back to life and then made him escape to attack the coach, but he has no idea why.
The younger Monro returns with a coffin, old and damp, that he places on a table in the auditorium. The older man goes to help him and Martha follows to watch what they are doing. She hides behind a row of chairs until they leave, then approaches the coffin. A plaque reveals that the contents of the coffin are John Monro (1670-1740).
A frightened congregation huddles inside the church. The Reverend Yarwood is troubled that the church will not stand up to the assembled corpses outside. Some of the congregation are less than confident in the reverend’s judgment in general. When the corpse of the previous Reverend, a man named McVicar, appears at the window one of the congregation opens the door to him.
Martha is discovered by the two Monros. The younger man attempts to attack Martha but the older knocks him to the floor with one of the batteries. He tells Martha it was his wish to bring back his father who had so much in his life that was not completed. Martha tells him that his own son is the one he should worry about. The older man says that he has no son. Both the Monros hold up their hands. They are identical, and the left hand of each is the same as all the other disembodied hands that she has seen.
McVicar enters the church. McAllister orders his men to shoot but the Doctor steps in the way to prevent them, pointing out that the corpses only attacked last time after the soldiers opened fire. Yarwood locks the door on the rest of the corpses who, like McVicar, are standing inert. Using his sonic screwdriver the Doctor notes that McVicar is dead, apparently animated by high levels of static electricity. This leads him to part the dead man’s cl othes and find a hand sitting over his heart. When McVicar suddenly makes to leave one of the soldiers panics and seems ready to fire a shot at him. McAllister is ready to let this happen (after all the man is already dead) but the Doctor uses his screwdriver to emit a piercing sound. The corpse crumples to the floor. This coincides with the hand falling from its purchase on the man’s chest. The Doctor has only just picked it up when the corpses outside begin to assault the church, triggered (the Doctor surmises) by the hand coming free from its host. McAllister decides that the majority of his men will stay inside the church to engage the corpses while the youngest married soldier, Howkins, will lead the civilians to safety. The Doctor comes up with an alternative plan – he will step outside to show the others that the hand is alright. McAllister looks at the Doctor with growing respect and tells him that he will come out with him.
Monro explains the origin of the hand top Martha. Thirty years earlier it had been found by a Brewster, at which point it had not looked like a hand at all. It had adopted the shape of a hand, albeit a mechanical version, before Monro purchased it. In its sleek, black form it had dug its nails into him, drawing blood, and then transformed into the image of his own hand. After he began experimenting on the hand with elect ricity it split in two, one hand attaching to his leg until it grew into a younger replica of him. Now Monro and his younger twin intend to reanimate their father as a baby to resume his work. Martha is deeply critical. She points out that the younger Alexander Monro is not the same man as the elder, and therefore any facsimile of his father will not be the same. It seems as if the older man will agree with her when the younger screams. The fingers that emerge from his breast twitch violently and the two hands he holds grip him tightly. A deep bass rumble announces a landslide of hands pouring into the room. Martha grabs the elder Monro and a stray hand. They flee but the younger is buried within a ball of flesh.
Behind them the hands have come to a form of consciousness, caused by the sonic burst. They have remembered that their true purpose is to join together and merge around a single whole. Noticing that one of their number has been taken they discover anger, develop legs and give chase.
The Doctor faces the corpses with the hand held out in front of him. They all stand back. McAllister points out the damage that they have done to the church. He states that they must not be allowed to reach the Castle. Using his screwdriver, the Doctor checks the corpses before slapping his head and shouting, “Benjamin Fr anklin!” He points out that Franklin once drew a cartoon called Unite or Die that showed a snake cut into pieces, intended to show the American Colonies that they must unify. Then blowing up a balloon he asks McAllister to rub it to create a static charge. Giving the balloon to the hand that he holds he watches as the hand bursts the balloon then races to the nearest corpse, where it climbs up to the hand at her heart. There it merges with the other hand and falls to the floor. As if they all understand the hands all drop from their corpses and begin to join into larger hands. The corpses drop to the floor once their hands have gone. The Doctor explains that the hands were not creatures in their own right but cells, intended to cling together and form a larger creature. Faulty information had made them cling to the dead, but he has repaired them now. By now the hands have combined into two bear-sized creatures and are heading across the Loch. McAllister and the Doctor decide they must follow.
Martha tells Monro that they have to get to the Castle. They are pursued by the monstrous shape of the hands that encircle the younger Alexander Monro. They race through the streets and up the Royal Mile, then under the Royal Exchange through the underground streets of Mary King’s Close, which Monro tells Martha is open at the Nor’ Loch end. In the dark warren of houses Martha loses Monro and20then drops the hand that she was holding: it scuttles off. In a patch of light she sees another figure that of a man with a raven’s face.
As the Doctor and McAllister paddle over the Loch they see the two hand creatures climb out ahead of them and merge into a giant man shape which jogs off. They reach land and chase up the hill, following the sounds of surprised shouting to track their prey. Eventually they follow the dark passages under the Royal Exchange until they meet Martha. The Doctor says that the beak-faced man is a plague doctor from a hundred or more years earlier. A hand leaps from the apparition and runs to the two giant hand men that are also in the room now. Behind them the old Monro is pinned to the wall by disembodied hands. The two creatures merge into one.
The Doctor asks it if it can speak now. Eventually it announces that it is Onk Ndell Kith and that it crashed into the planet many years earlier. Now that it is whole again it says it needs to affect some genetic repairs that will require the DNA of some 80,000 people (approximately the population of Edinburgh). The Doctor suspects that this repair will have to be effected again in a century or so, but he suspects that Glasgow will do for that. He tells Kith that there is another way. He offers his own Time Lord DNA as an alternative, because it is self-regenerating. Martha objects but the Doctor tells her that she should take what is left of him back to the TARDIS and activate the Laika Protocol, but not to be offended if the TARDIS calls her Rose. Then he offers his hand to the creature.
Kith starts to sift through the Doctor’s DNA and RNA and sift through his memories. Then it abruptly stops and races off through the streets. The Doctor is suddenly appalled as he realises that it is making for the TARDIS: a much better option than being a stranded Time Lord would be if it could become a living time-ship. The Doctor pulls out his screwdriver and says he will try to use it to disrupt the electric field that is holding the hands together. Monro determines to protect his younger self and grabs the screwdriver before running off. Martha gives chase. She catches up with Monro as he arrives at the foot of the Castle walls. Kith is nearing the top of the wall. Monro calls out to it but it merely detaches a hand which drops to the old man and starts to strangle him. He drops the screwdriver. Martha picks it up and uses it to paralyse the hand which she kicks away. Then she turns the screwdriver on the giant Kith. It begins to tremble and hands fall off, dropping to the floor around her. As soon as they a re out of the line of fire they recover and begin to attack Martha. The Doctor arrives above her and tells her to turn the screwdriver off. As soon as she does so the hands climb up and rejoin the larger creature.
The Doctor is standing on the wall a few feet from the TARDIS. He has taken a reel of wire from the TARDIS and is holding a flag. Kith climbs over the wall and sees the blue box. Once again the Doctor offers himself instead of the TARDIS. Martha, Monro, McAllister and a party of soldiers arrive. The Doctor has made the flag into a kite and attached it to a thin metal wire with the TARDIS key attached. He launches the kite. One of the hands in Kith’s leg holds tight to the wire and the Doctor exhorts Alexander to keep hold. The kite sails into the clouds and the key soaks up the electricity of the impending storm before transferring down the wire to Kith. Electricity plays over his body as the Doctor tells Martha to use the screwdriver. Kith disintegrates into a shower of smoking hands, dropping over the wall into the Loch below, leaving Alexander Monro on the ground. The Doctor tugs the wire and the TARDIS key drops down to him.
Edinburgh 1997. The Doctor is showing Martha where the Loch once lay. He tells her how it was filled in and the Scott Monument built on top of it. He also tells her that the reanimated Arthur King was chasing Franklin’s coach at the start of their adventure because Franklin had one of the hands.
Edinburgh 1771. Freed, by his experiences, of his fear of death, and his search for immortality, the younger Monro reclaims the last hand of Kith from Franklin. Franklin offers his condolences on the death of Monro’s father but the young Alexander says that with him around his father will never be truly gone.