Human Nature ( TV story ) Human Nature was the eighth episode of the third series of " Doctor Who " . It introduced the Chameleon arch and its ability to change Time Lord DNA , making the Doctor human . The episode was based on a novel of the same name . Synopsis . In England in 1913 , school teacher John Smith experiences amazing dreams of living an incredible life as a mysterious adventurer called " the Doctor " , fighting monsters and seeing far away worlds . Plot . The Tenth Doctor and Martha barely make it into the TARDIS as an energy weapon discharges behind them . After ascertaining that their pursuers had not seen their faces , the Doctor explains that they are being pursued by aliens who have stolen a Time Agent ' s vortex manipulator and can follow the TARDIS anywhere . He gives her a watch and tells her his life depends on it . . . In November 1913 , at the Farringham School for Boys , schoolteacher John Smith wakes up from this dream . Martha comes in as his maid to bring him breakfast and addresses him as " Dr John Smith " . He explains to her that he sometimes has dreams of being an alien adventurer from another world , and she was with him . He notices the watch on the mantelpiece of his bedroom and Martha looks up eagerly , but he replaces it idly whilst remarking how easily dreams seem to slip away . He does , however , remember that it took place in 2007 , but she shows him a paper showing he ' s in 1913 and he ' s completely human . Outside , a column of boys in grey trousers and black coats march in formation to the front of the school , which is an elegant if rather old building , as a hymn is sung by another chorus . Smith , wearing a long black coat and hat , leads them through a history lesson regarding the end of the Napoleonic Wars . Elsewhere , Martha and fellow maid Jenny scrub the floors and are accosted by two particularly unpleasant cadets , one of whom makes a snide remark regarding Martha ' s skin colour . She doesn ' t rise to it , though remarks that she ' d like to smack him upside the head with her bucket once he ' s out of earshot , and Jenny notes that in a few years , boys like them will be running the country . Martha , her face sad , responds quietly that with the year being 1913 , they might not . Later , Smith runs into Matron Joan Redfern , the school ' s nurse , and they chat about the boys . She wonders if he ' ll be going to the local village dance and he rather awkwardly falls down the stairs . Martha comes to check up on him but Redfern casually dismisses her as a maid , under the assumption she has no medical knowledge . Smith talks about dreaming that he has two hearts but a stethoscope easily shows this is not the case . He shows Joan his journal of his various dreams and the creatures he has seen such as Dalek s , Cybermen , and the TARDIS . He also has pictures of Rose , although she disappears from the later entries . Nurse Redfern leaves with the book and when Martha goes after her , she asks how Martha came to be there with Smith . Meanwhile , a group of John ' s students are studying in their dormitory room . One of them , Timothy Latimer , is bullied by a fellow student , Hutchinson , who compels him into doing his Latin homework with a daunting deadline — the next morning . He proceeds to bully Latimer further as much for his obvious intelligence as for his uncanny and unsettling ability to know things he shouldn ' t or couldn ' t possibly know , like where Hutchinson ' s father is posted while serving abroad . Another student , Jeremy Baines , tires of teasing Latimer and announces to Hutchinson and the others that he knows the location of a secret stash of beer in the woods . He sneaks out the window to bring some back for the boys to enjoy in secret . Outside the local pub , Martha is complaining to her fellow maid , Jenny , that it ' s not fair that they have to freeze outside just to have a beer . Her modern attitude amuses Jenny , who wonders where she gets such ideas . Martha then notices a green light shooting through the sky . John Smith arrives and greets them , explaining shooting stars to them . Martha doubts the explanation in this case , being exceptionally careful to protect him . She runs off to investigate with Jenny following her . Baines has just found the cache of beer , in the woods near the school , when he sees a strange green light land on the field nearby . Curious , he investigates the light source , and stumbles across an entrance to the an invisible spaceship . Martha and Jenny arrive just moments after the ship briefly becomes visible , but miss seeing it as the cloaking technology turns back on . Inside the ship , Baines talks with the spacecraft ' s occupants , whom he can ' t see . They call themselves the Family . He wonders why he cannot see them , to which the Family ask why he would what to see them . Baines answers that it ' s because he wants to know what they look like . A raspy female voice explains that it can be easily done , as soon they will look " very " familiar . Baines screams in terror . Hutchinson and the other boys are getting impatient back at the dorm when Baines returns , his search for the secret stash of beer apparently being " unsuccessful " . He is also behaving unusually , sniffing the air as though he has a cold . His eyes are also open completely , but none of the other boys seem to notice , saying there ' s another stash somewhere else . Martha rides out on a bike to an old hut . Inside is the TARDIS , on reduced power . She enters and greets the time machine , something that makes her think she is cracking up now . Martha thinks back to how the Doctor warned that their pursuers would never stop following them . He gave her a watch saying it contains " me , " and said the Family ' s life spans were running out so they only needed to hide until they die . She remembers how the Doctor used a chameleon arch to rewrite his biology and transform himself into human . The TARDIS took care of everything else , creating a new identity for him . She turns on a recording the Doctor made prior to enacting his plan . She reviews it , but finds nothing pertaining to the strange sighting . She now worries that she may have to bring the Doctor back if they have found them , as it was the last resort the message said to use in that scenario . Joan asks John to sketch her in his journal , being surprised at how beautiful she is in his eyes . They kiss as Martha walks in on them by accident . She excuses herself , mumbling that love wasn ' t on the Doctor ' s list . She finds refuge in the TARDIS , and reviews the instructions again . The instructions are notably lacking one thing : the Doctor did not foresee that his human self might fall in love , obviously something he " never " thinks of . However , she is more concerned about the strange green " shooting star " , something the Doctor didn ' t mention either . On the subject about " John Smith " falling in love , Martha is annoyed and depressed that it wasn ' t her he fell in love with . Meanwhile , Latimer is summoned to John ' s office to retrieve a book . While John looks for it , Latimer is drawn to the pocket watch that contains the Tenth Doctor ' s Time Lord memories and abilities . The boy opens it , briefly seeing the Doctor ' s world , and strange voices speaking of a " Time Lord , " but closes it quickly as he hears Smith approaching . Latimer slips the watch into his pocket and as he touches the book Smith is handing him , he suddenly gets visions of the Doctor on the prowl . Smith notices that Latimer seems a bit off - kilter , but the boy excuses himself and scurries away , unnerved . Also inside the school is Baines , who senses a trace of a Time Lord . He telepathically reports to the others the status of the Doctor ' s whereabouts , and declares that it ' s time to activate the soldiers . On nearby Oakham Farm , Mr Clark confronts a scarecrow that has just appeared on his property . He conceives it merely as a practical joke pulled on him by an one of the " idiots " at the school . When he pulls the straw out and sticks his hand through the other side , he finds they are just scarecrows . Many more animated scarecrows promptly surround him . He becomes the Family ' s Father . Meanwhile , another young girl , Lucy Cartwright , is walking down a road when yet another scarecrow picks her up , frightening her . She becomes the Family ' s Daughter . Smith is giving weaponry training to the boys when the Rocastle , the school ' s headmaster , arrives and orders firing to cease . Hutchnison tells him they could do " " a lot better " " , as Latimer is being " " deliberately shoddy " " , at least according to him . He denies this , telling the headmaster he is trying his best , to no avail . He also speaks of his discomfort with the targets , which are meant to represent African tribesmen who would stand very little chance against machine guns when all they carry is spears . Dismissing Latimer ' s ' soft - hearted ' beliefs , Rocastle orders for firing to continue . Meanwhile , Latimer is haunted by a vision of the future where him and Hutchinson are under attack in the upcoming war . As Hutchinson ' s patience is getting beyond the limit , he requests permission to take Latimer off for a " " beating " " . Per Smith ' s countenance , the boys head back towards the school . Shortly after , Baines sniffs rather loudly , prompting Smith to ask if anything ' s the matter . He quickly dismisses it , although not in a normal fashion . On a walk together , Redfern informs Smith that he wrote about a war starting the next year , but he dismisses the idea , hoping peace will reign . As he continues talking , he notices a woman and her carriage getting dangerously close to a piano on a rope . Instinctively seeking to save her , John grabs a nearby boy ' s cricket ball and tosses it to start a chain of events that stop the woman just as the piano comes crashing down just feet away from her . Joan is impressed , but Smith says it was luck . He then asks her to the dance that night . Walking back to the school Joan tells John that she thinks that " the Doctor " is the kind of man he wants to be and his dreams are his subconscious ' way of trying to get to be so . They notice a scarecrow askew and John fixes it . Joan asks him where he learned and he reflexively says Gallifrey . However , when questioned about its location , John isn ' t sure . Meanwhile , the possessed Baines , Mr Clark and Lucy use their animated scarecrows to capture Jenny , who becomes the Family ' s Mother . Jenny then returns to the school and engages Martha in conversation . Martha quickly realises something is off about her friend and makes a hasty excuse to leave , barely avoiding a laser that ' Jenny ' fires at her from the upstairs window . She runs to Smith , who is with Redfern preparing to go to the village dance that evening . She finds that the watch is gone , and tries in vain to restore him to his Time Lord configuration without it . However , Smith assumes Martha is delusional and thinks his fictional stories are real . Annoyed , Martha slaps Smith , telling him to wake up . Smith , shocked at Martha ' s behaviour , promptly fires her and leaves for the village dance with Nurse Redfern . The Family break into Smith ' s office and search it , as the scent is traced back to him . They find the flier for the dance and decide to follow . At the same time , Martha has arrived with the sonic screwdriver , prompting Joan to admit she feels something off about Smith . Tiring of Martha ' s " games " is left speechless when she shows him the device he ' s seen in his dreams . Latimer is still watching Smith from a distance , curious about him . The Family crashes the dance after vaporizing the unfortunate door attendant , to the confusion of the assembled villagers . Mr . Chambers , the man in charge of the dance , accosts Mr . Clark and asks him what is going on . In response , ' Clark ' disintegrates him in front of the horrified villagers . Martha quickly tells Smith to forget everything she just told him as the Family turn their attention to him . However , Lucy / Daughter of Mine has been there the whole time and overheard Martha ' s attempts to get the Doctor ' s memory back , telling her Family the Time Lord is within their grasp . However , John easily points out that he is human without any memories of the person he was before . Baines / Son of Mine is amused , seeing the Doctor went as far as erasing his memory along with changing his biology . As the Doctor is useless to them like this , they try forcing him to change back by threatening him . Remembering Martha said Joan was important to him , the Family takes both hostage and order John to choose which is to die : " Maid or matron , friend or lover , your choice . "