Zoe Heriot Zoe Heriot was a young scientist from the late 21st century who accompanied the Second Doctor and Jamie McCrimmon in their travels aboard the Doctor ' s TARDIS . She was one of the very few companions of the Doctor ' s that was as smart , and at times smarter than the Doctor himself . They would often compete with one another when tackling situations that required their intellects . Biography . Early life . Born circa 2069 , Zoe was taken from her family as a young child and subject to harsh mental and physical conditioning for brilliant children in a scheme known as the Elite Programme . She later became one of its chief opponents . ( AUDIO : " The Memory Cheats " , " The Uncertainty Principle " , " The Dying Light " ) When she was eight years old , she read Oscar Wilde ' s complete works , including " The Picture of Dorian Gray " , in a day . ( AUDIO : " Echoes of Grey " ) Meeting the Doctor . Zoe ' s home was a terrestrial city later shown to her in the White Void . ( TV : " The Mind Robber " ) At age 16 , she was an astrometricist first class and astrophysicist on board Space Station W3 ( a . k . a . the Wheel ) when she met the Doctor and Jamie in 2079 . ( AUDIO : " The Uncertainty Principle , Dying Light " ) She introduced herself to them as " astrophysicist , pure mathematics major " , to which her colleague , Dr Gemma Corwyn , added " with honours " . Zoe had an eidetic memory . She was described by her colleagues as " the librarian " . She was very bad at history , as evidenced by her lack of knowledge of the Dalek s , the Ice Warrior s , and the T - Mat fiasco . ( TV : " The Wheel in Space " , " The Seeds of Death " ) Having been taught only the value of logic , her training left her emotionally underdeveloped . This lack of balance led to conflict . Some of her colleagues challenged her about her apparent lack of personal interest in the Wheel when it was about to be struck by meteorites . When she met the Doctor , Zoe was presented with a case study in how illogical , intuitive actions and instinct could be successful . As Zoe became aware that there was more to knowledge than facts , she decided to hide in the TARDIS . She realised that she had learnt as much as she could on the Wheel , where her abilities and role were compartmentalised and defined . Zoe was ready to discover the universe and her place in it . Before he felt ready to have her brave the terrors of the universe , however , the Doctor showed her a thought projection of his most recent encounter with the Dalek s . ( TV : " The Wheel in Space " ) Travels with the Doctor . In 2724 , two beams of energy from a pulsar hit the TARDIS , causing it to forcibly land on a nearby planet . The TARDIS had landed in a human base where humans in the Fifth Galactic Surveyor Corps could observe an ancient city on the planet orbiting the pulsar . The base was under attack by a force that had killed some of the crew . The Doctor stayed behind to open the door to the surface for the rest of them to escape to , as the outside door could only be opened from the control room . The Doctor eventually left the base , and explained he had made contact with the force , the Quiet One s , and agreed to a truce in which Sophie ' s team could continue to safely learn about and communicate with the Quiet Ones , if they did it more quietly . While minutes had passed outside , for the Doctor it was a few years . ( AUDIO : " Shadow of Death " ) When visiting the War Museum on Dulkis , Zoe was reminded of " the old atom test islands on Earth . " At the same time , she was dismissive of the Quark s , claiming , " They ' re only robot s . " ( TV : " The Dominators " ) In the White Void , Zoe was lured out of the TARDIS by seeing her home city on the TARDIS scanner screen . Having recognised the Karkus from the Hourly Telepress of the year 2000 , Zoe was able to defeat him in unarmed combat and secure his loyalty . ( TV : " The Mind Robber " ) She used her programming skills to solve problems . Whilst helping the Doctor and Jamie deal with the Cybermen ' s invasion of Earth , Zoe destroyed the computer in the reception at International Electromatics . Determined to not be beaten by the " brainless tin box , " Zoe gave the computer an insoluble program in ALGOL , and delighted in the computer ' s destruction . With her logic and mathematics , Zoe computed the attack pattern for missiles to set up a chain reaction to destroy the incoming Cyberships . ( TV : " The Invasion " ) She spotted a cyber - ship escaping the explosion of the fleet and the Doctor decided to follow it . Landing on Isos II she encountered giant slugs which she enjoyed riding . While investigating the city she got trapped in a lift . Investigating the train line with slug trails on in she encountered Cybermen but was rescued by Hilsee . Taking her to a place of safety he showed Zoe what had happened to his people . She saw a half converted cyberman and felt appalled . She was told by Hilsee that there was no way to escape . The Cyber - Controller ordered her conversion . As Hislee was the one to put her in the pod he didn ' t fasten her in which allowed her to escape . ( AUDIO : " The Isos Network " ) Jamie and Zoe had an argument about there being no peaceful aliens in the universe . She found the Integral weird to look at . When she discovered what Aspen Base was built for she said that more Integral were needed due to the failure of the experimental machine the humans were using to replace them . ( AUDIO : " The Integral " ) When Zoe explored a cave on Sanctuary she found that there was maths everywhere , some of which she couldn ' t understand , that ' s because they came from Gallifrey . She spent ages trying to decipher the equations as Stoyn had taken the Doctor with him . She eventually realised that the equations where like a computer programme . ( AUDIO : " The Dying Light " ) Zoe ' s great knowledge and intellect were always evident , but never more so than when she was tested on the teaching machines used by the Krotons to teach and indoctrinate the Gond s . Having scored more than double the score of the best Gond students , Zoe declared the Doctor could certainly answer the questions too . ( TV : " The Krotons " ) The Doctor took her and Jamie to England in the 1960s to investigate a spate of mysterious robberies . She helped him to find out who was behind it . After stopping them the Doctor placed her memory into the crystal as its user guide for UNIT . ( AUDIO : " Tales from the Vault " ) She used her technical skills to get some of the equipment of Tromesis and found out that a meteor was heading towards them . She was later taken by a Hawker to the other version of the city due to an experiment by physicists which accidentally created two versions of the city . She told the Doctor about this . ( AUDIO : " The Apocalypse Mirror " ) Again using her computational and logic skills , Zoe , in further travels , worked out the trajectory of beacon segments to deduce that a band of space pirates must have their base on the planet Ta . ( TV : " The Space Pirates " ) The group landed in the Frenko Bazaar , a famous intergalactic trading post where one could buy " just about anything " . After the Doctor and Zoe rescued Jamie from a kidnapping , the trio teleported back to the shop . The Doctor was shocked to find his companions missing , having been captured by Adam Mitchell . ( COMIC : " Bazaar Adventures " ) Later , all eleven Doctors rescued the companions and sent them back to their own times . ( COMIC : " Endgame " ) At some point during her travels with the Doctor and Jamie , they visited Bob Dovie at 59A Barnsfield Crescent in Totton , Hampshire on 23 November 1963 . ( AUDIO : " The Light at the End " ) She liked to try and understand parts of the TARDIS such as the Relative Dimensional Stabiliser and teased Jamie when he couldn ' t understand . With the Doctor she took a test to gain access to the labs on The Edge . When Provost Curtis saw her sore he wanted to keep her in his Acuman mine . Jamie eventually rescued her from being kidnapped by him . ( AUDIO : " The Edge " ) The Doctor and his companions landed on a planet where the War Lord s planned to use human soldiers as an army to conquer the galaxy by picking them out of various periods of Earth ' s history with the the War Chief ' s space - time vessel technology that had been given to them . The Doctor , Jamie and Zoe helped unite the various resistance movements on the planet to fight the War Lords . Unable to return the soldiers himself , the Doctor sent a hypercube to the Time Lord s to return them to the right time zones . After the capture of the Doctor ' s TARDIS dematerialisation of the War Lord for his crimes , the Time Lords sent Zoe back to the Wheel , where she was met by Tanya Lernov . Having had her memory of her time with the Doctor and Jamie removed , other than her initial adventure with them on the Wheel , she was never aware that she had ever been away . ( TV : " The War Games " ) Life after the Doctor . Whilst she was working on the UrtiCorp Project at station XZ49 , the Third Doctor arrived , pretending to be an academic named Dr John Smith . But when Zoe saw the TARDIS , she collapsed , because the sudden return of her memories caused her to lose them completely , as a result . When she recovered , the Doctor had already left , suspecting that the Time Lords sent him there to make sure she forgot all her memories of the Doctor . ( PROSE : " The Tip of the Mind " ) After discovering she had aged by two years after the only experience with the Doctor and Jamie she could recall , Zoe deduce d she had had more adventures with the Doctor which had been wiped from her memory . About a month after her return to the Wheel , the Wheel was attacked by a Cybership . Due to her slight build , Zoe was judged unfit for conversion into a Cyberman , but upon scanning her brain and recognising her above - average intelligence , the Cybermen decided she would be suitable for conversion into a Cyber - Planner . The conversion caused Zoe ' s memories of the Doctor to resurface . It also gave her the opportunity to gain control of the systems of the Cybership . Before the conversion was complete , Zoe had diverted the ship into the only place she could think of where the Cybermen would be unable to hurt anyone else — the Land of Fiction . Once there , she took control of the Land ' s damaged computer , bringing the Land of Fiction back to life . She used fictional characters and constructs to fight the Cybermen , but came to the conclusion that she needed the Doctor ' s help to triumph over the Cybermen . After unsuccessfully attempting to create an accurate fictional version of the Doctor , she opened a hole in space - time and sent a data - stream which drew the TARDIS into the Land . The TARDIS landed far off - course , so Zoe created a fictional version of Jamie to protect the Doctor as she drew him to her control centre . With the Doctor ' s help , she destroyed the Cybermen once and for all . As the Doctor returned her to the Wheel , the Time Lords ' conditioning of her mind returned and she lost her memories of him once more . ( AUDIO : " Legend of the Cybermen " ) As the years passed , Zoe began to have detailed dream s of her adventures with the Doctor and Jamie . Unable to clearly remember her dreams or reconcile them with the knowledge that she had parted company with the Doctor when the TARDIS left the Wheel , she undertook psychiatric counselling . ( AUDIO : " Fear of the Daleks " ) In her late fifties , Zoe lived alone , unable to form relationships as a consequence of the damage to her memory . At this time she was approached by a young woman , Ali , who claimed to have met the Doctor , Jamie and the younger Zoe at the Whitaker Institute in Australia . With technological assistance , she was able to recover Zoe ' s recollection of that adventure . It transpired that the Company which owned the Institute had become aware of Zoe ' s history as a time travel ler , and were seeking knowledge of what she had learned . Zoe refused to cooperate with them , but suspected that they would not let the matter rest . ( AUDIO : " Echoes of Grey " ) Her fears were justified ; the Company engineered her arrest on charges that carried the death penalty , threatening to have her executed unless she could prove she had travelled in time and share the secret of time travel with them . During this time an employee for the company named Jen was responsible for helping Zoe recover her lost memories with the help of a machine . With Jen ' s help , Zoe is briefly able to remember some of her adventures with the Doctor , but forgets all about them once again after the sessions are over . In spite of the memories recovered during her sessions , Zoe stubbornly maintains that she had not travelled with the Doctor , claiming the Company was trying to discredit her as mentally unstable . ( AUDIO : " The Memory Cheats " , " The Uncertainty Principle " ) When it became clear that Jen was making no progress with Zoe , the company sent in Kym , the woman who had originally posed as Ali when the Company first approached her . Having pioneered the technology used to recover Zoe ' s memories , Kym had lost her standing with the Company due to her past failure with Zoe and was attempting to succeed where Jen failed in getting the secret of time travel from Zoe . During their session , Zoe recalled an instance where the TARDIS landed on a space station called Artemis . While there , she decoded the last transmission from Artemis ' s sister station , Apollo , before it was destroyed . The transmission contained a virus capable of transferring itself to living tissue and other matter , apparently responsible for the destruction of space station Apollo , where it had been developed . Zoe attempted to quarantine the virus , but was knocked out when a computer terminal hit her during a meteor shower . In the end the Artemis was destroyed along with most of the crew as the virus ate away at the space station itself . Zoe was able to survive , however , thanks to an air mask given to her by a guard , keeping her alive when she was sucked out into space before being rescued by the Doctor and Jamie . Kym realised that the events that Zoe witnessed were already happening in their current timeline as news of Apollo ' s destruction reached them , which turned out to be a Company - owned space station . Wanting to rectify her mistake of accidentally releasing the virus onto Artemis , Zoe agreed to go with Kym to prevent this disaster on the condition that she tell the Company the secret of time travel afterwards . Kym and Zoe were taken to the ship by Jen , with Zoe posing as a guard . As the events began to unfold , however , Zoe began to realise that Kym was behind most of the events that unfolded during her original visit to Artemis with the Doctor . In the end , Zoe found out that Kym only brought her to the space station so she could finish decoding the virus and make a copy of it for Kym to give to the Company to get back in their good graces . After tending to her younger self and providing her with a breathing mask to survive the destruction of the space station , Zoe pursued Kym into the escape shuttle . There , she was able to send a modified version of the virus to the Company ' s headquarters where it would take out the Company ' s entire computer mainframe and then self - destruct before it could spread to any organic matter . In the process , the virus was also released into the escape shuttle , destroying it as Kym gave up her own breathing mask to keep Zoe alive before pushing her out of the ship into space , where she was eventually recovered by Jen . Now free of the Company , Jen continued to help Zoe recover her memories , even as they seemed to become increasingly hazy for her . ( AUDIO : " Second Chances " ) Illusion . When the Second Doctor , accompanied by Brigadier Lethbridge - Stewart , was sent to the Death Zone on Gallifrey , Zoe and Jamie appeared to the pair in the Tomb of Rassilon and warned the Doctor against going further in the direction he had chosen because they said that they were in a force field . Knowing the Time Lords had erased their memories of him , he realised that they must be an illusion . This was proven right and they both vanished . ( TV : " The Five Doctors " ) When he was trapped in the maelstrom by the demon Melanicus , the Fifth Doctor saw an illusion of Zoe playing a carnival Hoopla . ( COMIC : " The Tides of Time " ) Personality . Despite knowing very little about the Doctor , she was a very loyal companion . She described him as old , clever and kind . ( AUDIO : " The Five Dimensional Man " ) Although brave , she was quick to call for assistance if she needed it . ( TV : " The Seeds of Death " ) When visiting her recent history , Zoe became irritated by the out - of - date technology that they used . ( PROSE : " The Wheel of Ice " ) She was also a maths wizard . ( TV : " The Wheel in Space " , TV : " The Krotons " ) She was a vegetarian . ( AUDIO : " The Integral " ) Jamie considered Zoe to be " a nice enough lassie " but was irritated by her occasional smugness . ( AUDIO : " The Edge " )