The Doctor and Martha, perused by gunfire, flee into the TARDIS and hurriedly take off. The Doctor makes sure their pursuers saw neither of them before discovering that they are being followed through the time vortex. He realises there is only one possible way to stop them and presents Martha with a fob watch

“Take this watch, my life depends on it. This watch Martha, this watch…”

John Smith awakens in his bed. He gets up as his maid Martha enters with his breakfast. He tells her of his recent extraordinary dreams of being a space-traveller known as the Doctor, dreams in which she has also played a part. He picks up his fob watch from his mantelpiece and identifies it as also being part of his fantasy, before remembering that his dream took place in 2007.

Martha hands him the morning paper, reading out the date of “Monday 10th November 1913”

In an English Boarding school Smith, a teacher, walks the corridors and teaches his lessons, whilst Martha and her companion Jenny go about their cleaning work, heckled by the senior boys of the school.

Some time later Smith carries a large pile of books around the school, encountering the school matron on the way. She helps him with the load and together they make their way around the school, Matron (alias Nurse Joan Redfern) taking the opportunity to ask him if he will be attending the annual local dance. He begins to splutter a reply but manages to fall down the stairs before he can give an eloquent response.

Soon Joan nurses a wound on the back of his head in his study, Martha rushing in to make sure he is not harmed. Seeing all is well she begins to tidy his things whilst Smith recounts to Joan his dreams, wherein he is a man hiding from someone, he dreams he is a man with two hearts. Joan takes her stethoscope and examines his chest, playfully confirming he has only one.

He presents her with a journal of his dreams; a diary filled with scribbled writing and drawings of all manner of creatures some human. Martha looks on keenly and follows Matron out, trying to prevent her from reading the book, but to no avail.

In one of the school dormitories sit three boys, Baines, Hutchinson and a younger boy named Latimer. Hutchinson reads a letter from his father, and Latimer correctly manages to pre-empt that he has been stationed in Africa, despite knowing nothing of the man himself. He admits that he has in the past managed to predict things before knowing them, but the others ignore him. Baines decides to retrieve some concealed beer in the woods, and hurries out of the window.

That night Martha and Jenny sit outside the local pub, Martha somewhat annoyed at not being allowed inside with the men, and takes refuge in the fact she will be leaving in a month’s time. Suddenly she sees a bright green light in the sky, but Jenny denies it. However, in the woods not far away Joan, who is walking alone, is suddenly bathed in a vivid green light, which proceeds to scan the surrounding area like a searchlight.

Joan hurries to the pub, were Smith joins her. Together with Martha and Jenny they see another light falling to Earth, which Smith claims is a meteorite. He leaves with Matron whilst Martha runs off to find where the light came down.

In the woods, Baines is distracted from his work by an eerie green light descending from the skies. He nervously goes to find it but finds himself in an empty field. Suddenly he is stopped in his tracks by an invisible wall, which glows to the touch. He manages to locate a gap in the surface and wanders inside, disappearing from view.

Moments later Martha and Jenny arrive but find nothing, and returns wearily to the school whilst inside the invisible structure, which appears to be a ship; Baines is interrogated by sinister bodiless voices. He asks to know what they look like and moments later a scream rings out. He arrives sometime later back at the school, an unnatural look on his face. He sniffs around the room as Latimer looks on curiously, shining his shoes.

The next day Martha cycles into the woods, arriving at an abandoned cottage in which stands the TARDIS. She steps inside to find the ship illuminated only by the central console, the walls surrounding it are dark. She remembers arriving in the ship, chased by some unnatural force. She recounts the Doctor’s words to her:

“Martha, this watch is me”

He had explained to her that the creatures were chasing him, the last Time Lord in existence. To avoid them he had to become human. He used a helmet that descended from the ceiling, the chameleon arch, to change his own biology and store what made him a Time Lord inside the watch.

She looks up at the device still suspended from the ceiling in the darkened ship and she remembers his screams of agony. His cries of pain that rang around the ship as a new life was set for him and all that he was became stored inside the watch.

Finally she moves over to the scanner, playing back the last recording he made for her before the change; a list of instructions for what to do whilst he remains human. She scans them but finds nothing regarding meteorites in the sky, and is left alone in the hollow room.

Back at the school Latimer calls on Smith to borrow a book. Whilst his teacher searches for the title the young boy sees the watch the mantle, he opens it temporarily as voices swarm around his head, and as Smith returns he places it in his pocket. He retreats back to his room and opens the watch, a bright light emitting from within and the voices returning.

Outside Baines appears to sense the disturbance, and when he returns inside he reports back to the ship that a source has been detected, and the soldiers must be activated.

In a field not far away a man named Mr Clark sees one of his scarecrows moving. Thinking it to be one of the schoolboys he reaches inside the lining to grab them, finding only a handful of straw. Bemused he looks at the figure, which grabs him as others like it spring to life across the field. On a road nearby a small girl with a balloon walks along, but is confronted by a scarecrow, who carries her away, screaming.

Back at the school Smith oversees the boys practising to fire machineguns at dummy targets. Latimer and Hutchinson arm the weapon, the former appearing to experience a vision of war, himself and his colleague fighting in the maze of barbed wire and mud. He observes his watches and claims that the “time is now”.

Breaking from his fantasy Hutchinson takes him away to be beaten, whilst Baines simply sniffs at his teacher, Smith. Matron appears from inside and Smith moves to speak to her, finding her upset by thought of her husband who was killed in war.

Together they leave the school and walk through the local town, discussing the idea of war, a premonition Smith appears to find in his dreams. Suddenly the teacher observes an accident waiting to happen, a piano being hauled to a first floor window is about to fall, a woman with her pram slowly walking into it’s path.

He grabs a cricket ball from a nearby by and throws it at some scaffolding nearby. It pushes the poles aside, upsetting a plank of wood on which lays a brick. The brick launches into the air and upturns a milk urn, which falls in front of the pram, preventing it from moving further into the space where the piano falls.

Smith appears marvelled by his own capabilities and suddenly finds the courage to invite Joan to the village dance. Soon they are walking through the fields together, discussing the character of the Doctor. Smith sees a nearby scarecrow and moves to correct it on it’s perch whilst Joan compliments him on his drawing, provoking him to mention his home in Gallifrey, a place she assumes to be in Ireland. Having finished correcting the scarecrow the two walk off, unaware that it turns to watch them go.

Back in his study Smith sits and draws Joan in his journal, eventually moving to kiss her. He begins to mutter some excuse but she kisses him again, as Martha enters unannounced and sees them. She flees back to the TARDIS to consult the Doctor’s instructions but finds nothing to explain what she should do.

“You had to go and fall in love with a human…and it wasn’t me.”

At the school, Latimer sits with the watch and listens to the voices, stooping to observe Baines, Mr Clark and the young girl with the balloon meeting on the other side of the grounds. On a road not far away Jenny is ambushed on her bicycle, surrounded by the animated scarecrows.

Soon she is inside the alien ship, Baines introducing her to his mother, a glowing green orb. He claims that she needs a body and suddenly a green gas emerges from the orb, overcoming the poor servant.

Smith and Joan prepare for the ball as Jenny returns to her quarters, where Martha awaits. She sniffs unnaturally as Martha confesses her concern about Smith, who is to leave the school in a few weeks. She begins to realise that Jenny is not herself and hurriedly leaves. However, Jenny draws an alien gun and pursues her, firing at her as she flees.

She returns to Smith’s room and tells him they have been found. She tries to find the watch but it appears to have gone. Smith believes her to be having some sort of breakdown and patronisingly explains the situation to her, only for her to slap him in an attempt to bring him round. He grabs her by the arm and pushes her outside, dismissing her from his service. He then returns inside, where Joan tells him that Martha was not lying about the watch, it has gone.

Martha runs outside, bumping into Latimer (who appears to have a subsequent vision of the same incident occurring in Martha’s own time zone). She hurries back to the ship and rummages in the Doctor’s coat, as Baines and Jenny arrive in Smith’s now-empty quarters looking for him.

Smith and Joan meanwhile arrive at the village dance, closely followed by Latimer. As they dance around the room Baines and Jenny continue to search the school, before Mr Clark produces the poster for the dance. Jenny smiles, her daughter is already there.

At the dance the girl with the balloon watches the entertainment as Martha arrives, unaware the scarecrows are watching from the surrounding fields. Inside she confronts Smith and presents the Doctor’s Sonic Screwdriver, ordering him to identify it. She tries to explain to him that he isn’t John Smith; he is the Doctor, the man from the journal.

Soon Baines, Jenny and Clark arrive, storming the venue and shooting anyone who disobeys their orders for silence. Martha orders Smith to be silent as Baines turns on him, realising that the Doctor has taken human form. Smith fails to understand and Baines threatens to shoot him if he doesn’t change back. Jenny and Clark grab Martha and Joan and point guns at their heads. Baines offers him the ultimatum:

“Your friend or your lover. Your choice.”

The family continue their demands but Latimer distracts them by momentarily opening the watch. Martha takes one of the family’s guns and aims it at Baines, taking Jenny hostage. Eventually the family release Joan and together with Smith she flees alongside the other guests. Martha stays behind but drops her gun and runs when one of the scarecrow soldiers attacks her.

Baines orders Clark, his father, to find the Doctor’s ship and the others make their way to the school, where the Smith, Joan, Martha and Latimer have already returned. Smith raises the alarm for the students to take up arms despite Martha’s protests. Outside the family arrive and Baines sends his sister to find a way into the building.

Smith warns the headmaster of the oncoming danger as the boys continue their preparations and Martha runs to find the watch, which Latimer cradles beneath one of the staircases, the device appearing to talk to him, warning him to keep the Doctor safe.

Outside the headmaster and his aide arrive to confront Baines, Jenny and the scarecrows. He tries to warn the attackers to leave but they demand to have Smith handed over. Baines then warns the headmaster that in the following year, 1914, a war will come and the boys of the school will fall in the mud of foreign fields:

“Do you think they will thank the man who taught them it was glorious?”

The headmaster returns to the school after Baines shoots down his colleague, whereupon Smith tells him the phone lines have been cut; they are on their own. He orders the boys to continue preparing but Baines too is ready, ordering his scarecrow army to march on the building.

Upstairs Martha explains to Joan that the watch contains all that makes the Doctor a Time Lord, and then proves to her the strength of her medical knowledge, which the nurse initially appears to doubt. The nurse then returns to the boys downstairs as the father of the Family of Blood contacts Baines and claims he has found the Doctor’s TARDIS, he cannot escape.

Smith encounters Joan in the corridor and she begins to question his morality, finding him unable to reveal more than encyclopaedic facts of his childhood home. She then tries to appeal to him, asking him not to send the boys to fight but he claims he has no choice.

Outside Latimer and Hutchinson are aiding the preparations, and Tim reveals another of his visions, that the two boys will fight together in the approaching war. Hutchinson seems not to understand and looks on as Latimer runs off, concerned about why the watch appears to talk to him.

Inside it tells him to beware the daughter of the Family, and sure enough she is soon on his tail. He opens the watch in an attempt to ward her off but in doing so he transmits it’s significance to the rest of the Family, who realise that the watch is all they need.

Soon they are advancing on the school, battering on the barred gates. The boys await the command to attack and Smith too raises a rifle. However as the scarecrows break in and the boys open fire, he is unable to release a single shot. The army are ploughed to the ground but soon the daughter arrives. Martha rushes outside to warn the headmaster not to go near her but he neglects the warning and she shoots him down.

Smith refuses to let the boys shoot her and orders a retreat. Baines arrives to reanimate his soldiers and chaos brakes out as Latimer and the other boys evacuate the school. The Family begin searching for the watch but Latimer again distracts them by opening the watch, fleeing as they begin to chase his tail

Smith, Martha and Joan make their way outside and conceal themselves in the bushes. Nearby Clark stands with the TARDIS, ordering the Doctor to come out of hiding. Smith claims never to have seen the blue box before but Joan reasons that it is part of one of his dreams. He begins to panic, fearing the accusations that he is not just John Smith. He flees whilst Baines and his family move off to launch the next stage of their attack, and as Joan leads Smith and Martha to an abandoned cottage, the Family return to their invisible ship, preparing their armaments.

Inside the cottage Smith is distraught, realising he must surrender himself before anyone else dies. Joan protests but soon Tim arrives with the watch, claiming it wants him to return it to the Doctor. He turns to Smith and recounts what he has learnt of the Doctor from the watch:

“He’s like fire and ice and rage. He’s like the night and the storm and the heart of the sun…He’s ancient and forever. He burns at the centre of the time and he can see the turn of the universe…and he’s wonderful.”

Joan produces Smith’s journal of his dreams and theorises that they may be more than stories. Soon the Family open fire on the village with bombardment shells and Smith takes the watch, suddenly talking as if he were the Doctor, claiming Latimer’s special powers are simply abnormal levels of psychic ability. Reverting to his usual speech pattern, Smith reels back and turns on Martha, who he claims merely sat and watched as he fell in love, despite knowing she would have to “execute” him.

She claims that such a thing was not in the Doctor’s instructions for her and he scoffs at the thought of a man who doesn’t think of love. She explains that the Family of Blood has a limited lifespan, and that the Doctor went into hiding to wait until they had died. She confesses that there is more to the Doctor than Smith thinks, and reveals how special he is to her; although she’s only known him for a short time and although she hopes he never hears her confess it; she loves him.

As the bombardment gets closer Smith claims he can simply give the Family the watch and not die in order to bring back the Doctor, but Joan cuts in, having realised that should they gain the watch they will be able to live forever, and that cannot happen. She asks Martha and Latimer to leave for a moment and once they are gone she embraces her distressed lover.

Joan insists that Smith must open the watch, even if the Doctor will not love her the way he does. She takes the device and he in turn holds her hand. Suddenly they see what could be if the Doctor were to remain human; Smith and Joan would marry and have children, live happy lives until their old age and then die peacefully. Back in the present Joan protests that the Time Lord could never have such a life and then finally asks what Smith has decided to do.

Some time later he arrives on the Family’s ship. He bumbles around, accidentally activating some of the controls. He offers them the watch and Baines takes the device, but upon opening it he finds it empty. The Doctor has tricked them.

No longer a human, the Time Lord drops his act and reveals that his pratfalls weren’t for nothing, he has activated a self-destruct sequence. He flees the ship and soon the family follow, a giant explosions throwing them to the ground. They look up into the night sky, as the Doctor stands over them, and Baines recounts what happened next.

“He never raised his voice, that was the worst thing. The fury of the Time Lord. And then we discovered why, why this Doctor; who had fought with Gods and demons, why he had run away from us and hidden. He was being kind.
He wrapped my father in unbreakable chains forged in the heart of a dwarf star. He tricked my mother into the event horizon of a collapsing galaxy, to be trapped there forever. He still visits my sister; once a year, every year. I wonder if one day he might forgive her…He trapped her inside a mirror. Every mirror. If ever you look at your reflection and see something move behind you, just for a second, that’s her. That’s always her. As for me, I was suspended in time, and the Doctor put me to work standing over the fields of England as their protector.
We wanted to live forever, so the Doctor made sure that we did.”

And after leaving Baines, now a scarecrow, the Doctor returns to the abandoned cottage, where Joan is waiting. He tells her he has finished his work as she struggles to get used to seeing the man she once loved in a different form. She asks if he might ever change back and he claims that although he could, he wouldn’t. She tells him Smith was a braver mad than he is; whereas the Time Lord chose to change John Smith chose to die.

The Doctor asks her to come with him in the TARDIS but she refuses, even if Smith does live on somewhere within the Doctor. She asks him if people would still have died had he not arrived in England, but he cannot answer. He leaves her alone with Smith’s journal, returning to the TARDIS as tears form in her eyes.

Finding Martha waiting for him the Time Lord announces it is time to go, and she takes the opportunity to dismiss her previous declaration of love as an attempt to get Smith to change. He agrees and then thanks her for looking after him. They embrace as Latimer arrives to thank them, now knowing his future and what he must face. The Doctor gives him the now-empty watch and after saying goodbye the two travellers leave.

“In June 1914 an archduke of Austria was shot by a Serbian. And this then led to nations having treaties with nations, like a line of dominoes. And some boys from England walking together in France one terrible day…”

The following year, in the muddy fields of battle, Latimer and Hutchinson walk together. Latimer observes his watch and notes that now is the time. He looks to the sky and pulls Hutchinson to the ground, narrowly avoiding an artillery strike. He looks to the sky again and thanks the Doctor, before walking off with his friend.

And some ninety years later at a memorial service, an elderly Latimer sits in a wheelchair, still holding his watch. He looks off into the distance to find the Doctor and Martha standing close by, and he smiles.

“We will remember them.”