Companions who are introduced in the Fourth Doctor era.
Surgeon-Lieutenant Harry Sullivan (Fourth Doctor)

A surgeon lieutenant at UNIT, of the old-fashioned gentleman variety. Originally posted to UNIT from the Royal Navy as a medical orderly, he joined Team TARDIS after the Brigadier told him to keep an eye on the Doctor, which Harry took to mean "across time and space". Had a habit of getting stuck down gentle slopes and being attacked by entirely stationary animals.
- Adaptation Species Change: The Doctor Who 3 - The Third Motion Picture short story set in the continuity of the Peter Cushing films has a senile Doctor Who take on a new companion called Hari Sullivan who turns out to be a yeti in disguise.
- The Artefact: He was written out for this very reason. It was initially believed that the Fourth Doctor would be played by an older actor, so Harry was meant to be the strapping male lead who would do the heavy lifting. Tom Baker's casting muted this, so Philip Hinchcliffe felt that he was a bit redundant. However, he came to regret this decision due to Harry's popularity.
- Badass Normal: No matter what Four says, Harry had his badass moments.
- Brainless Beauty: He's very handsome and enjoys a flirtatious dynamic with Sarah Jane, but it often seems like he has very little going on between both ears. He's obviously not meant to be thick, considering his medical and military qualifications, but that's nonetheless how he comes across.
- The Bus Came Back: After his departure as regular character in "Terror of the Zygons", he made one more appearance later in the season, in "The Android Invasion" (the last 1970s UNIT story to feature any recurring characters from the organisation).
- Captain Obvious: Part of why people see him as an idiot is that he's prone to useless observations, most notoriously in "The Ark in Space" when Noah is having a mental breakdown over the radio.Harry: The chap sounds in a bad way.
Sarah Jane: (rolls eyes theatrically) - Distressed Dude: All the time. Infamously got nearly eaten by a Skaro clam, despite clams not exactly being known for their high velocity or their predatory abilities.
- Genius Ditz: He's a trained medical doctor and a high-ranking UNIT official, so you would expect him to bring some relevant expertise to the table. This is undermined by the way he's written as an Idiot Hero.
- Genre Refugee: According to Terrance Dicks, he was supposed to be a ridiculous, over-the-top Boy's Own adventure hero who had somehow found himself in a Doctor Who story, being narratively upstaged by the Doctor and not quite able to realise why this is happening to him. He doesn't really scan as this after "Robot", due to other writers taking his genre quirks more seriously.
- Idiot Hero: He could be quite clumsy and unsubtle. This led the Doctor to declare in a moment of frustration, at the top of his lungs that "Harry Sullivan is an imbecile!", before passing out from the effects of a rockfall on Voga – caused by Harry.
- Informed Ability: He's a doctor (a literal one of medicine), but always seems out of his element. The Doctor teases him about it and jokes that Harry's only qualified to operate on sailors. Big Finish states that he ends up working as a virus researcher for NATO. Later, in The Sarah Jane Adventures, Sarah Jane confirms that after his time with the Doctor, he did pioneering work with vaccines, saving thousands of people.
- Just Following Orders: His reason for joining the TARDIS crew.
- The Medic: He's medically trained, but his intuition fails him at some key points, such as when he incorrectly assumes that the cryogenically-suspended passengers in "The Ark in Space" are dead and refuses to believe when the Doctor says otherwise.
- Mildly Military: He's a Royal Navy Surgeon-Lieutenant, but he rarely ever acts like it.
- Nice Guy: A polite and friendly gentleman through and through, albeit with some old-fashioned views. Unfortunately, the Fourth Doctor abused Harry's docility at every opportunity.
- The Nicknamer: Continually referred to Sarah Jane as "Old Thing" and had similar nicknames for other characters.
- Omnidisciplinary Scientist: He's a naval surgeon, who helped develop a life-saving vaccine, as well as a chemical weapon to wipe out the Zygons.
- Quintessential British Gentleman: "I say!" He has a number of such old-fashioned catchphrases and mannerisms.
- Remember the New Guy?: He's first introduced as an established member of UNIT, who's apparently already very familiar with the Doctor. In fact, the Brigadier makes a phone call to the medical officer "Lieutenant Sullivan" in the story before his actual debut.
- '70s Hair: He rocked the sideburns look way before the Tenth Doctor.
- Stealth Insult: Quite bad at picking these up whenever he's on the receiving end. He was quite delighted by the Doctor's sarcastic compliment about his mind improving until he finally registered it as an insult.
- Straw Misogynist: Can be pretty sexist and condescending towards Sarah Jane. This was deliberate by the production team in order to contrast with Sarah Jane's Straw Feminist traits.
- Unfazed Everyman: He takes everything in his stride.
Leela of the Sevateem (Fourth Doctor)

A human Noble Savage, descendant of an ill-fated colonization expedition and genetically altered into a perfect warrior. Primarily remembered for her Fanservice leotard and trying to kill anything that looked hostile — however, though she was (initially) quite ignorant, she was definitely not stupid and made up for her lack of knowledge with her own insights, kindness and Simple-Minded Wisdom.
- Action Girl: Her first instinct when faced with trouble was to hurt things until trouble went away again.
- Anti-Hero: Unlike the Doctor, Leela doesn't have any qualms about hurting or killing others. The Doctor caves in during their third story together and just lets her kill whatever's attacking them.
- Badass Adorable: Leela is a complete badass who can certainly hold her own and rarely feels fear, but she's also an enthusiastic and compassionate person who really wants to learn from the Doctor and this results in a lot of adorable moments of her curiously listening to the Doctor explain science.
- Badass Boast: She has some of the most memorable in the series.Leela: Before I die I'll see this rathole ankle deep in blood. That is a promised thing.
- Blood Knight: A rare example of a blood knight who's both female and one of the good guys.Leela: Enjoy your death, Rutan! As I enjoyed killing you!
- Bound and Gagged: In "The Talons of Weng-Chiang", in Episode 6.
- Cargo Cult: The Sevateem turn out to be the descendants of a crashed Survey Team, and ended up worshiping their own broken technology after a few generations of mucking about in tents.
- I Choose to Stay: She remains on Gallifrey and marries a Time Lord named Andred after the events of "The Invasion of Time".
- Combat Pragmatist: As she says in "Face of Evil":The Doctor: You wouldn't want an unfair advantage, would you?Leela: Yes.
- Contrasting Replacement Character: Leela was specifically created by Philip Hinchcliffe to be a more proactive character after hearing a little girl say that she identified more with the male Doctor than the female Sarah Jane. Whereas Sarah Jane was a clued-in but physically delicate Muggle Best Friend, Leela was an intelligent but undereducated Nubile Savage who the Doctor tended to pick on as an inferior and who specialised in intuition and violence.
- Conveniently an Orphan: Her father dies in their very first scene, taking the tribe's trial instead of her after she's convicted for heresy.
- Depending on the Writer: When first introduced, she was relatively uncivilised but in fact highly intelligent (she is shown as abandoning all superstition when the Doctor explains science to her). In "The Robots of Death", she immediately understands what's going on with Poul, but lacks the cultural context to articulate it to any characters other than the Doctor. In "The Talons of Weng-Chiang", she caught on the nature of the villain almost as quickly as the Doctor. Bob Baker and Dave Martin, on the other hand, saw her as just uneducated and stupid and struggled to use her - in "The Invisible Enemy" she's described as 'all instinct and emotion', and in "Underworld" by the same writers she gets hit by Stun Guns and spends most of the story acting stoned as comic relief. Compare to "The Sun Makers", in which she is also comic relief for most of the story, but able to understand fairly sophisticated economic situations.
- Detect Evil: Has the ability to sense evil.
- Expanded Universe: Though Leela subsequently gets name-dropped by the Doctor in a couple of TV stories (and in an "I wonder how Leela's doing" context), she doesn't return for real until the audio play "Zagreus", where she teams up with Time Lady President Romana. The two then went on to star in their own spin-off which ran from 2004-2013. Big Finish also sees her starring in several seasons of the Jago & Litefoot series.
- Fur Bikini: More precisely, a leather leotard and knee-high boots. Actress Louise Jameson once showed off a letter she received from a young girl viewer asking if Leela would "please wear more clothes". In a scene filmed for the Series 5 DVD release, Amy Pond comes close to uttering the trope name when she asks if Leela (seen in a photograph) is wearing a "leather bikini".
- Genre Refugee: She's a character from an Edwardian Jungle Opera novel, to go with her Gothic Literature-themed Doctor. She's from a Cargo Cult worshiping Ancient Astronauts (albeit with a twist), uses all of the Noble Savage and Nubile Savage tropes and her name is a play on 'Leila', the stereotypical name of foreign Femme Fatale characters of Two-Fisted Tales of this era. She also takes influence from the Pygmalion Plot, to the point where she was originally conceived as a Victorian Cockney flower girl.
- Good Is Not Soft: Undoubtedly, Leela is on the side of good and is a decent person deep down, but try to kill her or the Doctor and you'll end up with a knife or Janus Thorn in the neck.
- Hot-Blooded: Don't make this woman mad. Adelaide Lessage and Lord Palmerdale found that out the hard way in "Horror of Fang Rock" when Leela smacks Adelaide across the face just for screaming and threatens to cut out Palmerdale's heart.
- Jerk with a Heart of Gold: Not really a mean person at all but instead extremely blunt and prone to using violence as a solution due to her upbringing, but Leela is actually a deeply compassionate and sweet person who selflessly tries to protect others particularly the Doctor constantly.
- Jumped at the Call: Simply walked into the TARDIS and pushed buttons until she was a companion, despite the Doctor's protests.
- Mayfly–December Romance: Andred is Gallifreyan, and thus Human Outside, Alien Inside and Long-Lived. In the audio series, she ends up outliving him by many years.
- Nerves of Steel: Her "fight or flight" response has no "flight" setting. She screams exactly once (not counting war cries), and that was when a giant mutant rat started chewing on her leg. Louise Jameson is on record saying she crossed out every instance of "Leela screams" in her scripts except for the aforementioned giant rat gnawing on her leg.
- Noble Savage: Very proud and headstrong.
- Nubile Savage: Didn't wear a lot of clothing most of the time.
- Only One Name: As with the rest of her tribe.
- Poisoned Weapons: The Janis Thorn native to her home planet, that inflicts immediate paralysis and swift death; the Doctor banned her from using them, but she continued to do so behind his back on at least one more occasion in "The Talons of Weng-Chiang" as well as expanded universe appearances.
- Psycho Sidekick: She kills or inflicts potentially-lethal violence on quite a number of mooks, and the Doctor's protests often seem only token.
- Pygmalion Plot: The original idea (without the "falling in love with her" bit). Leela defies the trope by learning just enough about technology and manners to get by, but intentionally staying very true to her savage origins. On more than one occasion, she ends up convincing others that her way of life is just more fun.
- Refusal of the Call: Much like the Fourth Doctor, she has zero desire to become the president of anything after she's accidentally elected, and — with a quick Screw This, I'm Outta Here! — runs off in the TARDIS instead.
- Screaming Woman: Defied. The times she's screamed in terror can be counted on one finger, specifically when her leg is getting eaten by a monstrously-sized rat in "The Talons of Weng-Chiang". She tends to plot how to kill/defeat the baddies every other time.
- She Cleans Up Nicely: Her Victorian dress in "The Talons of Weng-Chiang" and "Horror of Fang Rock", both serials which are infamous in the American Doctor Who fandom for their own individual reasons.
- Silent Snarker: Becomes one briefly in "Horror of Fang Rock". After she sees Adelaide faint, she rolls her eyes with a "done with this shit" look on her face.
- Simple-Minded Wisdom: Upon encountering some Three Laws-Compliant robots, she snarkily posits that the second law must be "men cannot harm robots" — since they obviously can't be stabbed.
- The Strategist: She's extremely adept at planning war tactics (though many of them in the end come down to "stab things really hard", although in her defence it isn't as if the Doctor travels with a company of archers or an artillery battery). "The Talons of Weng-Chiang" has her striking out on her own without the Doctor for a while, during which she manages to navigate Victorian London on her own and find exactly the allies she needs.
- Transhuman: Her tribe was the result of an ill-fated eugenics experiment involving two groups of humans. Her group had its courage and strength boosted; the other group got enhanced reasoning skills and telepathy.
- The Watson: One of the things that made her work so well as a companion- being a Noble Savage who had never had the opportunity to receive any kind of education beyond survival skills, she was ignorant of many things which required the Doctor to explain them to her, but she was still allowed to be very intelligent in her own right.
- What Happened to the Mouse?: Her fate in the Time War was unknown for a long time. In Big Finish episodes "The Catalyst", "Empathy Games" and "The Time Vampire", her decades spent on Gallifrey without aging start to catch up with her after Gallifrey is gone, and she lives out her final days reminiscing before dying in an alien prison. The announcement trailer for the Blu-Ray
release of Season 15 depicts a much older Leela on Gallifrey, at an unspecified point during the Time War. A soldier gives her the means to escape the war using a Wayfinder device, also informing her that it is The Doctor's wish that she save herself, before the soldier is exterminated by a squadron of Daleks. Leela guns a few of the Daleks down before making her escape with a smile on her face...and ends up teleporting right inside the Fourth Doctor's TARDIS!
K9 Mark ISpelling (Fourth and Tenth Doctor)

The first robot-buddy of the franchise, hailing from the 51st century. K-9 Mark I, the original built by Professor Marius, was a highly advanced robot built to resemble a dog. Known for his laser nose, propensity to speak in Literal-Minded terms, and his constant uttering of "Affirmative", or "Negative", which stuck with his descendants. He had a short run and remained with Leela on Gallifrey. This was because his prop's maintenance sucked. Prone to break even if it hit a simple bump on the floor, he was quickly replaced by Mark II. Mark I was later brought back in his own series but due to design copyrights, he got destroyed in a fight with the Jixen and regenerated through a special repair unit into a brand new appearance with Laser-Guided Amnesia to sever all explicit ties with the Doctor Who franchise.
Tropes associated with Doctor Who
- Badass Adorable: K9 is treated like a cute little dog by the Doctor (when the Doctor isn't grumbling over K9 being smarter than him), yet nonetheless is a capable thinker who can use his laser nose to easily stun enemies and destroy objects. This is best shown in "School Reunion", where K9 is doted on like a house pet by the Tenth Doctor yet nonetheless is the one who saves the day in dramatic fashion thanks to his cunning and his laser beams.
- The Blank: His face can't express any emotion at all, but his rotating "ears" and waggly tail can give himself away.
- Breakout Character: Like Sarah Jane, he got two spin-off television series, even if they were shortlived.
- The Cameo: The original K-9 hosted the 40th anniversary celebrations for the series while it was in its so-called wilderness years, voiced by John Leeson.
- The newly-introduced Mark IV, also played by Leeson, appeared on The Weakest Link in 2007 for a promotion of Series 3, but he was mostly a Joke Character who was voted off immediately. The reason was that the prop operators feared K-9's dreaded habit of breaking down at the most inconvenient times would happen during the game, so they made sure he would be voted off in the first round (the game's selection of DW cast itself admittedly agreed to rig their votes so that only members of the regular cast at the time were guaranteed to stay on till the final round and guest cast got the boot—but this didn't stop top-billed actors from being voted off).
- Also cameoed on Queer As Folk as the perfect gift for Doctor Who fan Vince, an Author Avatar in this respect of Who fan and future New-Who re-creator and showrunner Russell T Davies.
- Blatant Lies/The Time Traveller's Dilemma: Cameoed on an episode of Jim'll Fix It. In order to prevent Reapers from destroying London on account of a temporal paradox, had to pretend to be "pleased to meet Mr. Savile and chair".
- Canine Companion: The Doctor insisted on treating him like an actual dog.
- Catchphrase: "Affirmative." "Negative." "Master/Mistress?"
- Cute Machines: He is very adorable.
- Deadpan Snarker: He got into many a snarking match with Four.
- Do-Anything Robot: Laser beam, hacking computers, defensive protocols, beating the Doctor at Chess, being a Deus ex Machina...
- Family Friendly Firearm: K-9's ever-convenient laser beam has a kill option, but is always set on stun.
- Hyper-Competent Sidekick: Particularly if viewed specifically as The Doctor's sidekick.
- Insufferable Genius: He's a futuristic alien super computer, so he's just as smart as the Doctor. And he's well aware of it.The Doctor: We all make mistakes sometimes, don't we, K9?K9: Negative.
- Kid-Appeal Character: K-9 was a huge hit with children, which contributed to his longevity as a companion despite the notoriously unreliable prop being a constant thorn in the production staff's side.
- Made of Iron: Subverted, K9 gets damaged often despite his claims of not being made of tin.
- Non-Human Sidekick: Serves as a beeping Robot Buddy for The Doctor in the original series.
- Only Sane Man: K9 seems to cater to this. Being The Spock of the team, focusing on logical reasoning in everything he does, his clinical nature is a far cry from the Doctor's eccentricity and the quirks of his various companions.
- Pint-Sized Powerhouse: His laser weapon helps him take care of opponents often twice his size.
- Punny Name: Get it? K-9? Because it looks like a dog! K-9! As in CA-NINE.
- Robot Buddy: To the Doctor, Romana, Leela and Sarah Jane.
- Robot Dog: A medical robot, originally.
- Smart People Play Chess: In "The Sun Makers", K9 plays chess with the Doctor, with the latter attempting to show that his intellect is superior to any computer. K9 ends up winning anyway, with the Doctor too caught up in his own smugness to believe it.
- The Spock: Being a medical robot at heart, K9's programming prioritizes logical reasoning first and foremost, never acting on impulse and rebutting the Doctor's own rash decisions.
- Zeerust: His appearance would have been considered fairly tacky and retro even by the show's standards when he was first introduced. It's eventually lampshaded in "School Reunion".Rose: It looks so... disco.Tenth Doctor: Oi! In the year 5000 this was cutting-edge!
Tropes associated with Big Finish
- Brainwashed and Crazy: K-9 in Return to Telos when under Cyber-control.
- The Comically Serious: Sarcasm is completely lost on him, and would react to snarky remarks from the Doctor and his other companions at face value. Hilarity frequently ensues.
- Grand Theft Me: He's temporarily taken over by Zodaal in "The English Way of Death".
- The Mole: When infiltrating the Rocket Men.
- No Social Skills: He's basically a talking calculator on wheels and the one thing going for K-9 is that everyone thinks he's cute.
- Not Now, Kiddo: A running gag with the Fourth Doctor, who'd tell K-9 to be quiet just before k-9 has something important to tell him.
- One-Steve Limit: Discussed with the Doctor, when he gets very confused as to why K-9 refers to both The Doctor and The Master as "Master". He tells K-9 to call The Master "The Renegade".
- Only Sane Man: Likes to think of himself as this, but his complete lack of understanding humans leads to very awkward (and funny) situations, and averts this trope.
- Robot Buddy: At least on the occasions when he leaves the TARDIS at all.
- Sliding Scale of Robot Intelligence: Frequently displays Level 4 abilities in episodes like "Requiem for the Rocket Men", where he's able to do dozens of mathematical equations simultaneously in his head while assisting the Doctor in about three other difficult tasks.
K9 Mark II
K-9 Mark II was the replacement for Mark I, who would now only stun, not kill things (at least not living things - he does kill at least one robot). Affectionately referring to the Doctor as "Master", Mark II was conceived because K-9 was popular with the kids, but the prop needed a redesign after breaking down all the time. He stayed with Romana II when she stopped travelling in the TARDIS. John Leeson quit the role at the end of Season 16, so David Brierly was brought in for Season 17 as his interim voice actor. The change in his voice was Hand Waved as K-9 contracting robot laryngitis. Brierly quit after on season and Leeson returned for Season 18, on the understanding that K9 would be written out during the season.
Tropes associated with the television continuity
- Badass Pacifist: In keeping with the Doctor's morals, this K9's potentially lethal nose-laser was dialled down to only having a stun setting.
- Literal-Minded: More so than the Mark I.Romana: Uh, K-9, what is tennis?K9: Real, lawn or table, mistress?Romana: Never mind. Forget it.K9: Forget. Erase memory banks concerning tennis. [whirring sound] Memory erased.
- Replacement Goldfish: After K9 Mark I elects to stay with Leela on Gallifrey, the Doctor casually starts unpacking a boxed Mark II that he apparently kept around in case of this eventuality.
Tropes associated with Big Finish
K-9 travels with the Doctor, and Romana, but has on occasion been relegated to looking after the TARDIS while his Time Lord friends go out exploring. He eventually joins back up with Leela and Romana in the Big Finish spinoff Gallifrey. On one occasion, both K-9 and Romana, after establishing themselves on Gallifrey, rejoin with the Doctor for a once-off adventure involving Professor Chronotis.
K9 Mark III
K-9 Mark III was the model who got given to Sarah Jane Smith as a gift from the Doctor, in the One-Episode Wonder K-9 and Company. He turned up in a few comic stories and "The Five Doctors", and that was it (unless you count the non-canon "Search Out Space" and "Dimensions in Time"). He didn't appear again until 2006 in a few audio stories leading up to Sarah Jane Smith's return to the series proper, where he got badly damaged, fell into disrepair, and rusted in Sarah Jane's attic because she didn't know how to fix a robot dog with futuristic technology, nor could she reveal said technology to anyone before its time. Mark III's functionality was somewhat restored by the Tenth Doctor, long enough for him to give his life by defeating the Krillitanes.
Tropes associated with Doctor Who
- Awesomeness by Analysis: The Tenth Doctor and Sarah-Jane repair him so he can figure out what's on with the chips at a school they're investigating. Once he's fixed up, he works it out quickly.
- The Cameo: Briefly appears during "The Five Doctors", when we see Sarah-Jane leaving for work.
- Deadpan Snarker: What does he suggest Mickey do to break into the school?K9: We are in a car.
- Heroic Sacrifice: Blows up a bunch of Krillitane oil tanks, but in order to do so has to be right by the barrels.
- Spin-Offspring: Mark III's first appearance was in an obscure comic story and he prominently appeared alongside Sarah Jane in a failed spin-off pilot. His only appearances in the main TV series were a brief cameo in "The Five Doctors" and a more major role in "School Reunion".
- Took a Level in Badass: Thanks to an improved special effects budget, K9 gets to zap multiple Krillitane when he reappears in "School Reunion".
- Used Future: Unfortunately has this aesthetic by the time of his return in "School Reunion" thanks to years of neglect (which was justified since the Doctor gave Sarah Jane no maintenance equipment and the technology used to build K9 is several centuries too advanced).
- Zeerust: His retro-futuristic appearance is mocked by Rose and defended by the Doctor as "cutting edge" for the 51st century.
K9 Mark IV
K-9 Mark IV was given to Sarah Jane by the Tenth Doctor as a replacement for Mark III, along with a sonic lipstick inside his casing. Mark IV was better associated as Sarah Jane's K-9 than the Doctor's, and this loyal robot called her "Mistress". He sported a more computerized-sounding voice and did not have as many locomotion woes because he could hover up stairs. He served as Sarah Jane's loyal pet and had an ongoing rivalry with Mr. Smith, the Xylok supercomputer. However, licensing issues left him trying to close a black hole after a Switzerland experiment went awry for the first three seasons of the The Sarah Jane Adventures. Then, he had a more active role in the plot, until the Australian K-9 series came out and the licensing disputes resurfaced, causing him to go to college with Luke Smith and return to light roles in the show.
Tropes associated with Doctor Who
- Big Damn Heroes: During "Journey's End", since the Doctor has forgotten the TARDIS base code, Sarah-Jane calls K9 out to provide it.
- The Nth Doctor: While physically distinct, he's treated as being the same individual as Mark III as he has retained all of the previous model's memories.
Tropes associated with The Sarah Jane Adventures
- Big Damn Heroes:
- His cameo appearances prior to joining the regular cast mostly consisted of him teleporting in when Sarah calls for him to save the day, most notably at the end of Series 1.
- Luke and Clyde take advantage of this by bringing to life Clyde's highly detailed drawing of K9 to help fight off the Mona Lisa and the Abomination (it's a long story).
- Commuting on a Bus: Spends most of Series 1 in the aforementioned black hole plugging situation, but afterwards he increases in prominence, alternating between being a regular and a Drop-In Character.
- Put on a Bus: Leaves to accompany Luke to university. (Out-of-universe, written out due to rights issues following the beginning of the Australian K-9 TV show.)
- Replacement Goldfish: A positive depiction. He was specifically created by the Doctor as a gift to Sarah Jane to fill the void left by K9 Mark III, but thankfully Sarah Jane's relationship with Mark IV is just as close as with Mark III.
- Sesquipedalian Loquaciousness: Lampshaded on several occasions.K-9 (In reference to Mr Smith): Contact with that computer interferes with this unit's synaptic circuits.
Clyde: You mean he gets on your nerves.
K-9 (More assertively that normal): Affirmative. - Sitcom Arch-Nemesis: He doesn't like Mr. Smith and the feeling is very much mutual. The two seem to compete for Sarah Jane's affections in the same way as rival housepets. Their ongoing enmity could be partially justified by lingering distrust after Mr. Smith's Face–Heel Turn incident which led to them having an intense firefight in the attic.
- Spock Speak: "Affirmative Mistress".
K9 Mark 2
Tropes associated with the television continuity
- The Nth Doctor: Largely subverted in that, while each K-9 unit is essentially the exact same thing as the previous model, the version in the K-9 spinoff looks and acts drastically different.
- Spock Speak: Subverted, unusually enough. This K9 is actually capable of normal, modern-sounding slang.
Romanadvoratrelundar (Fourth Doctor)

A Time Lord, or more properly a Time Lady, like the Doctor, and therefore has multiple regenerations. (Two were seen onscreen, dubbed Romana I and Romana II by fans; the Expanded Universe added several possible thirds, one of which is seen left of the first two here.) Sent to assist the Doctor against his will in the search for the Key to Time, she was initially what one would call "book-smart": extremely well-educated (her academic record trounced the Doctor's), but quite young and with little practical experience. As such, she is the one companion who could serve as the Doctor's co-pilot with the TARDIS. Despite her initial inexperience, she eventually became a Distaff Counterpart to him before parting ways to assist people in an alternate universe. However, Expanded Universe sources indicate she would eventually return to Gallifrey and become Lord President.
Tropes associated with most incarnations:
- Always Someone Better: How the Doctor feels about her. At one point, she even builds her own sonic screwdriver (which he tries to swipe!)
- Character Development: Her first incarnation was cold, detached and focused purely on the mission. Once she regenerated, Romana loosened up considerably and became much more fond of the Doctor.
- Contrasting Replacement Character: Whereas Leela was an uneducated but resourceful and intuitive savage, Romana was the Doctor's superior in intelligence but with less life experience.
- Deadpan Snarker: Both of them were prone to this. The first Romana's snark was rather icy, whereas the second preferred good natured ribbing.
- Distaff Counterpart: To the Doctor. A wandering Gallifreyan who dresses oddly, has adventures and (eventually) carries a sonic screwdriver.
- The Fashionista: Loved trying on new outfits, sometimes a few different ones in a single episode. Mary Tamm designed her own outfit in "The Androids of Tara" and Lalla Ward came up with her own ideas.
- Known Only by Their Nickname: Romana's full name is only mentioned in two stories: her first appearance and her final appearance. In the novelizations, the fact that her full name is Romanadvoratrelundar might get mentioned a couple times in the early chapters, but she will still only be referred to by the shortened version in conversation.
- Only One Name: As with most Time Lords and Ladies. However, unlike many travelling Time Lords, she never adopts an alias, she just shortens her real name.
- Only Sane Man: Much more rational and level-headed than the Doctor.
- Overly Long Name:Romana: My name is Romanadvoratrelundar.
The Doctor: ...I'm so sorry about that. Is there anything we can do? - Vitriolic Best Buds: Grows into this with the Doctor, engaging in Snark-to-Snark Combat that gradually becomes more affectionate.
Romana I

The Doctor: What?
Romana I: You're capricious, arrogant, self-opinionated, irrational, and you don't even know where we're going!
The Doctor: Exactly!
A tall, leggy, dark-haired woman; the initial concept of her was a "Grace Kelly" sort of character. Had a penchant for armchair psychology. According to the Big Finish Audios, she regenerated when forces beyond her control were drawn out by the Key to Time and started to weaken her body, but she passed the reasons off as a whim.
Tropes associated with the television continuity
- Action Girl: Occurs unexpectedly in "The Pirate Planet" when she gets into a laser gun fight and wins.
- Agony of the Feet: Romana's fashion statement got the better of her when she made a really bad choice of shoes in "The Stones of Blood" and wore high heels in a terrain filled with rocks. Naturally, she switched to bare feet before the end of the first episode to alleviate the pain and then put on some pragmatic boots.
- Defrosting Ice Queen: She relaxes a lot over the course of her tenure.
- Dropped a Bridge on Her: Without actually getting rid of the character. Since she is part of the same race as the Doctor, she could regenerate and stay on as a character. However, the regeneration comes with no explanation and is a lot like a standard Put on a Bus. She doesn't even get a death scene. Romana just happily walks into the console room with a new face and announces that she's regenerating, in a completely new way that was never seen again; The Doctor is absolutely baffled. The Expanded Universe offered several possible explanations, which of course all contradict each other.
- Foil: The Doctor is very experienced in adventuring but barely managed to graduate from the Time Lord academy; Romana is new to the wider universe but is very accomplished academically.
- Identical Stranger: Princess Strella of the planet Tara.
- Love Redeems: The Black Guardian's minion the Shadow develops a bit of a crush on Romana.
- Naïve Newcomer: She's quite out of depth compared to the Fourth Doctor in her early adventures.
- Pimped-Out Cape: Made of white feathers — a gift from the Doctor on their first trip together.
- Rich Bitch: Quite posh and stuck-up, especially compared to Tom Baker's Doctor.
- Ship Tease: One Christmas Bonus Material short had the Doctor and Romana I very obviously kissing just out of view, following by a rather suggestive look from Tom Baker.
- Skilled, but Naive: Maybe even more intelligent than the Doctor, but lacks any experience. When she first sees a monster, it terrifies the life out of her. She gets better though.
Romana II

Shorter, with strawberry blonde hair. Still snarky, but a lot more bubbly and Constantly Curious. And if anything, her style flair got even more creative.
Tropes associated with the television continuity
- Bifauxnen: She dressed in men's clothing a lot, especially that red smart suit in "The Horns of Nimon".
- Catholic Schoolgirls Rule: Wears a very St. Trinian's style uniform in the "City of Death" serial. Lalla Ward, judging by interviews and the production notes, came up with the idea and had no concept that it was a fetish.
- I Choose to Stay: After three serials of trying to get out of E-Space, she decides to stay at the end of "Warriors' Gate" to help free a race of enslaved time-travelling lion people from slavery.
- Contrasting Replacement Character: Mary Tamm's Romana was aloof, uptight and very by-the-book. Ward's version is a lot more outgoing, playful and adventurous. Whereas Tamm's incarnation came across as a sheltered aristocrat, Ward's incarnation was a more eccentric bohemian as shown by the clothing.
- Deadpan Snarker: She snarks at Duggan in "City of Death" about his tendency to break a lot of glass, and regularly holds her own in Snark-to-Snark Combat with the Doctor (if not winning).
- English Rose: Sci-fi version. Played by Lalla Ward who has the right look (a pretty pale-skinned blonde), she was a refined, composed and soft-spoken Nice Girl, but also brilliant and strong-willed. She comes from Gallifrey, which is kinda Englandesque.
- Expanded Universe: Her Big Finish audio spinoff with Leela, appropriately called Gallifrey (which has its own tropes page), spans eleven years (2004-2015). Big Finish is also one of the various franchises to provide a third regeneration of Romana.
- Gendered Outfit: Wore a pink version of the Doctor's outfit at one point.
- Genre Savvy: How does Romana get out of having to work in a Dalek mine so that she can promptly get back to the plot? She stops one of her hearts and fakes her death.
- Hair of Gold, Heart of Gold: Well, hearts, technically, also strawberry blonde, but she definitely fulfils this trope.
- Lady of Adventure: More keen on adventuring than her first incarnation.
- Large Ham: Can get dramatic on occasion, especially during ham to ham combat with Soldeed on "Horns of Nimon".
- Nerves of Steel: An adventurous Time Lady, she likely acquired such nerves after "Destiny of the Daleks", she can get visibly frightened easily but is a Plucky Girl nonetheless.
- Nice Girl: Friendly, outgoing and way easier to get on with than the first Romana.
- Plot Hole: Her regeneration scene, written by Douglas Adams, is one of the series' most infamous ones. Basically, Romana shows up in Princess Astra's body and clothes and announces that she has regenerated, for no reason whatsoever. When the Doctor scolds her for copying someone else's body, she merrily cycles through a series of different bodies until settling on the Astra look permanently. This type of regeneration contradicted just about everything in the series, was never explained in any way on TV, and was never heard from again. The Big Finish Gallifrey series, dives into the question headfirst and offers a very good explanation. Other bits of the Doctor Who Expanded Universe have also taken a stab at it: the short story "The Lying Old Witch in the Wardrobe", for example, suggests the TARDIS forced her to in a fit of jealousy (after impersonating Romana during the events of "Destiny of the Daleks"). One novel also hints that she chose to Regenerate and thus, until she picked one she settled on, could cycle through bodies as she choose - unlike the Doctor dying from injuries.
- Ship Tease: Big time. The Doctor often gently teases her but is clearly very, very fond of her. The Australian commercials for Prime Computer made it more explicit with the Doctor proposing to Romana — and she says "Yes!" before he even finishes. It doesn't hurt that there was also some Ship Tease between Lalla Ward and Tom Baker. They even got married briefly.
- Tears of Fear: Before gathering Nerves of Steel, she's pretty melodramatic when interrogated by the Daleks in "Destiny of the Daleks">
- Took a Level in Idealism: Much more outgoing than her predecessor, she very much took after the Doctor.
- What Happened to the Mouse?: Whether she survived the Last Great Time War or not is unknown, in every medium - even Big Finish hasn’t answered that yet, though it confirms she was present during the early years of the Time War. Although last heard she was imprisoned in a pocket dimension by Rassilon for trying to assassinate him.
- Wholesome Cross Dresser: Romana seems to like wearing men's clothing.
- You Look Familiar: The actress was a guest star as Princess Astra of Atrios in the story immediately preceding her debut. This was referenced in-universe as Romana choosing that form to regenerate into.
Tropes associated with Big Finish
- Break the Cutie: Gets thoroughly broken while she is imprisoned by the Daleks. She recovers marvellously, but she carries the emotional scars with her for a long time.
- Cold-Blooded Torture: In "Gallifrey: Extermination" she performs this on a Dalek, causing it to actually ask her to have pity, before it eventually dies. Romana holds the Daleks responsible for the level in cynicism she took after being their captive for two decades and takes a cold delight in exacting her revenge.
- Fan Fic: Spends her spare time as Lady President by writing a rather transparent Doctor Fan Fic, about a man named "Sigma".
- Good Is Not Soft: Plots to kill Rassilon in the Gallifrey: Time War series. She comes close to succeeding, too, but he regenerates.
- Mercy Kill: In "Zagreus", Romana is fully prepared to perform one on the Eighth Doctor.
- Reasonable Authority Figure: The audio adventures see her becoming the Lady President of Gallifrey - which was eventually confirmed as canon in "The Day of the Doctor", although only in tiny print in the background of a scene.
- The Slow Path: She spends twenty years as a slave for the Daleks.
Romana III / Trey

Tropes associated with Big Finish
- Raven Hair, Ivory Skin: As is anybody played by Juliet Landau.
- Set Right What Once Went Wrong: She is willing to break all the known laws of time to travel back into Gallifrey's history and help her past self prevent her own apocalyptic future from coming to pass.
- Younger Than They Look: Trey comes from many centuries in Romana's future, but Leela points out that this new body actually looks quite a bit younger than her current one. Romana II is quite miffed by this.
Adric of Alzarius (Fourth and Fifth Doctors)

A snotty teenage maths geek from E-Space, annoying in the way that snotty teenage geek-boys usually are, but a well-meaning kid all the same. The Doctor saw him as an incompetent underling, despite the fact that Adric was an absolute genius when it came to maths — just one who had a lot of learning to do about personal skills. As a result, Adric felt ignored, unwanted and rejected, and tried coming up with his own creative solutions to solving each story's problems. Usually very unsuccessfully. It all came to a head when he had a falling out with the Fifth Doctor and demanded to be returned to his home in E-Space.
Unfortunately, the TARDIS crew ran afoul of a Cybermen plot to lay waste to future humankind, and just barely managed to throw their plans off course. After a very brutal battle against the Cybermen, Adric's fate was tragically sealed when he became trapped inside a crashing freighter on an unstoppable collision course with prehistoric Earth. After the TARDIS navigation controls were blown up by enemy fire, the Doctor and company could only watch the inevitable unfold. With no hope of rescue, Adric braced himself for the end, sharing his late brother's fate of an equally young and bitter demise. His loss devastated the Fifth Doctor, haunting him all the way to the very last moments of his life, and it deeply affected his fellow companions Tegan and Nyssa with pain and regret.
- All of the Other Reindeer: Adric is everybody's Butt-Monkey from the word go, and seen as an annoying tagalong more than anything else. At the start of "Earthshock," he actually confronts the Doctor about the way he's being treated by everybody, and how he's completely sick of it. The Doctor dashes out of the TARDIS as fast as he can just to avoid having to talk about those things.
- Anti-Hero: A bit of a jerk towards people at times. Notably, he felt that women aren't good for anything, which didn't exactly make him popular with fellow companions Tegan and Nyssa.
- The Artful Dodger: It's even part of his character concept.
- The Artifact: His "Artful Dodger in space" conception was obvious with the very Fagin-like Fourth Doctor. The changing of Doctors and the addition of Nyssa and Tegan undermined this and he jostled for attention afterwards.
- Berserk Button: He puts a girl in a stranglehold for trying to take his maths badge. In his first scene. It is a lot more heartbreaking in hindsight considering his ultimate fate, and how his badge ends up symbolically broken.
- BFG: Used for a very weakly executed but surprisingly effective one-man Big Damn Heroes moment near the end of "Warriors' Gate."
- Big Eater: A large amount of his character motivation throughout his time with the Doctor stems from just wanting to find some food.
- Bizarre Alien Biology: His Healing Factor.
- Character Tics: Due to his inexperience, Matthew Waterhouse never quite knew what to do with his hands while acting. His fidgety hands weren't meant to be a tic, but they come across as one.
- Contrasting Replacement Character: Whereas Romana was so competent that she often took charge and had the Doctor learning from her, Adric was a young boy genius who the Doctor was raising as a protege.
- Dying Alone: On a crashing spaceship, thinking he just failed to save the world.
- Expy: He was conceived as The Artful Dodger in space.
- Fake Defector: Considering he does this twice over the course of his time in the TARDIS ("State of Decay", and "Kinda"), it's not surprising that a lot of fans accuse him of "always siding with the villain." (He also has a habit of ''actually'' siding with the villain. Or being kidnapped by the villain and being forced to use his abilities for said villain. Or just stealing the villain's mecha and accidentally shooting at innocent bystanders...)
- The Friend Nobody Likes: Heavily implied to be the case among Five's companions, given how he seems to feel like an outsider to the group and how being an Insufferable Genius did little to help him get along with the others. It's Zig-Zagged however since the Doctor notably does try to connect with Adric and care for him, with Tales of the TARDIS and Big Finish both implying that while Adric might not have been liked by the TARDIS crew they still genuinely cared about him and were devasted by his death.
- Good with Numbers: He's the proud possessor of a badge for mathematical excellence and has demonstrated proficiency at the reality-warping mathematics that is Block Transfer Computation.
- Guile Hero: Becomes a plot point a few times.
- Healing Factor: You'd think it'd be a massively useful trait for a companion to have, given the scrapes they get into, but Adric's Healing Factor is only mentioned twice — in "Full Circle" (his introductory story) and again in "The Visitation."
- Human Aliens: Adric's species had three evolutionary forms, only one of which is humanoid.
- Iconic Item: His mathematical excellence badge. Seeing it shattered on the floor of the TARDIS at the end of "Earthshock" makes the Silent Credits all the more powerful.
- Informed Ability: For a supposed genius, Adric doesn't come off as being particularly intelligent. It's likely that, to use the classic Dungeons & Dragons metaphor, he's high intelligence, low wisdom (and charisma).
- Insufferable Genius: He very much wanted to be one of these, but his sheer incompetence at pretty much anything outside of mathematics pretty much scuttled the character. As such, he frequently came across as being more "Insufferable" than "Genius".
- Jerk with a Heart of Gold: To an extent. The "jerk" part doesn't really emerge until Season 19, but ultimately he still cares.
- Justified in the long run. He starts off in Season 18 in the shadow of the Fourth Doctor, who acts very smug, alien and impervious, making it hard to speak his mind, but Romana and K9 are also there to keep him in check, so he doesn't have to voice complaints. However, when Romana and K9 leave, Adric starts to voice his disdain, which is only furthered when traumatised Nyssa and especially argumentative Tegan join him as companions and the squabbling reaches a new high. Then the Doctor regenerates into his fifth incarnation, who is a lot more humbled, humane and vulnerable, removing the air of fear to speak out in front of him. Adric, of course, cuts loose on him.
- Limited Wardrobe: Wears the same yellow rompers in every single story.
- The Millstone: In "Castrovalva", he allies himself with The Master after being captured by him, and in "Earthshock", the whole plot is kicked off by him arguing with the Doctor over wanting to return to his home planet which eventually results in his death.
- Mr. Vice Guy: Driven by a desire for approval and acceptance. Whenever there's an older man in the plot, who's in charge, has a power complex and probably some kind of plan to take over the world, Adric will cling to the guy like a perfect little teacher's pet.
- Never Speak Ill of the Dead: Averted in the Tales of the TARDIS where after the Fifth Doctor and Tegan remember and discuss the events of "Earthshock", they laugh over how annoying Adric could be. However they also acknowledge that he was still a child and despite his intelligence his actions were that of a teenager trying to figure out his place faraway from home. Big Finish would also have the Doctor and Tegan discuss how annoying he could be while acknowledging that everyone is annoying when they're young.
- New Powers as the Plot Demands: Ability-wise, Adric is a surprisingly well-equipped companion, demonstrating proficiency in lock-picking, sleight-of-hand, and knife-throwing, amongst other things. The catch? Most of them only get used in one story, two if it's really lucky.
- Overshadowed by Awesome: He was constantly overshadowed by the Doctor, and basically everyone else in the room, for the entire duration of his stay in the TARDIS. He was introduced as a genius mathematician, but the Doctor, Romana and K-9 were all better at maths than he was, making him seem barely average rather than special. The initial idea had been to partner him up with Tegan, an 'everywoman' companion, after Romana and K-9's departure, but the spontaneous addition of the genius scientist Nyssa to the TARDIS (who was his equal in maths and good at more than just maths) made him doubly redundant. Many of his stories have him Trapped by Mountain Lions due to the inability to use him.
- Rummage Sale Reject: He wore ill-fitting pajamas with a rather childish star on the pocket and bright green boots.
- Senseless Sacrifice: A tragic case as Adric was trying to stop a ship from crashing with the Earth and he died thinking he failed to save all of humanity, not knowing that the ship was the meteor meant to wipe out the dinosaurs.
- Small Name, Big Ego: He certainly knows his stuff, but he doesn't have the smarts or the experience to back it up, especially compared to the Doctor.
- This Loser Is You: Conceived as somebody who the geek element of the fanbase would empathise with, but was too accurate a portrayal of a snotty, socially-inept teenage geek to appear in any way flattering.
- Took a Level in Jerkass: The fourth regeneration and the arrival of Nyssa and Tegan saw him seek attention and occasionally side with the wrong people, when he wasn't complaining and boasting about how smart he was.
- What Have We Ear?: He teaches the Doctor a few coin tricks.
- Wide-Eyed Idealist: The Doctor neatly summarizes it:Fifth Doctor: Now listen to me, you young idiot. You're not so much gullible as idealistic. I suppose it comes from your deprived delinquent background.
- You Can't Go Home Again: Because it's in a different universe. He's working on finding a solution when he dies.
Nyssa of Traken (Fourth and Fifth Doctors)
A teenaged scientist specializing in bioelectronics and the daughter of Tremas, who got his body possessed by the Master at the end of Fourth Doctor serial "The Keeper of Traken." Originally intended to be a one-off character for "Traken", the production team decided to make Nyssa a full-time companion and brought her back in the next story, "Logopolis", just in time to survive her entire planet being destroyed by The Master and to witness the Fourth Doctor regenerate into the Fifth. Stoic, level-headed and very handy with electronics, Nyssa was often portrayed as being wiser than her years, particularly in contrast to Adric, who was of a similar age and lived up to it much more than she did. One of the most accomplished TARDIS pilots among the companions; she was even able to fly it solo (with assists from Tegan in "Castrovalva" and Adric in "The Visitation").
- Advertised Extra: Even as a regular, Nyssa tended to have less to do than everyone else: unlike Adric, Tegan, or Turlough, she was rarely ever the focus of a story (though "Black Orchid" gave Sarah Sutton more to do by also playing Ann Talbot, the character of Nyssa was still comparatively minor), with the sole exception being her final appearance in "Terminus", a story that ostensibly put her centre stage but in reality mainly featured her looking ill and crying a lot. The character really ascended in the Big Finish audios, though, serving as the Fifth Doctor's most regular companion there and receiving tons of character development into the bargain.
- Ambiguously Bi: "Farewell, Sarah Jane" refers to "a nice couple from Australia, Tegan and Nyssa", but it's not clear if they're actually a couple. According to Big Finish Doctor Who she had a husband and two kids after leaving the Doctor.
- Angst? What Angst?: The implications of her tragic backstory are barely mentioned in the show, but the Expanded Universe would make use of all her emotional baggage.
- Ascended Extra: Was never intended to be a companion, until producer John Nathan-Turner decided otherwise.
- Beware the Nice Ones: "Arc of Infinity." She pulls a gun on the Time Lord President, among many others. Sarah Sutton notes in the DVD commentary how unusually trigger-happy Nyssa was in this story.
- Brainy Brunette: She was able to fly and repair the TARDIS, and could talk about space and time on the Doctor's own level, although she lacked his experience.
- Break the Cutie: She's had her planet destroyed and her father possessed by the Master, though her anguish over these things is very fleeting.
- Cannot Tell a Lie: While an expert on many subjects, Nyssa was not much use when it came to subterfuge.
- I Choose to Stay: She leaves the TARDIS crew to stay on Terminus and try to restructure it into a proper hospital.
- '80s Hair: A big mess of brown curls. Her later stories depict her having grown it out slightly and styled it into the Farrah Fawcett flip.
- Giant Poofy Sleeves: Her original outfit, but eventually done away with after her costume changes in Season 20.
- The Heart: One of the nicest, most compassionate companions ever to grace the TARDIS. This role was especially vital early on in her tenure, when the more fractious Adric and Tegan tended to clash with the Fifth Doctor.
- Human Aliens: Looks completely human, like Adric.
- Identical Stranger: Ann Talbot, a blue blood from The Roaring '20s.
- Innocent Aliens: From a planet where evil is outright banned, though woe betide anyone who mistook her innocence for stupidity.
- Innocent Fanservice Girl: Famous for the skirt removal bit in "Terminus," which the actor herself has described as "a gift to the fans".
- Last Of Her Kind: The rest of Traken died in "Logopolis" — though in the Expanded Universe book "Cold Fusion" there's mention of a Trakenite colony that survived.
- Leitmotif: "Nyssa's Theme"
combines a child's simplicity with the interwoven complexities of a brilliant mind. - Limited Wardrobe: Her burgundy velvet ensemble throughout Season 19.
- Literal-Minded: A running gag in the serials and audios is Nyssa's imperviousness to jokes.
- Nice Girl: Stands out among the Fifth Doctor's more bolshy companions as being sweet and compassionate to everybody.
- Odd Friendship: With Tegan, who is almost her polar opposite, and with Adric, who becomes like a little brother to her.
- Only Sane Woman: Out of all the Fifth Doctor's companions, Nyssa is the most rational, sensible and level-headed.
- Plucky Girl: Always eager to help out strangers or lend her scientific services.
- Pretty in Mink: One of her outfits had a fur-trimmed jacket.
- Proper Lady: Basically an alien princess, trained up in all forms of manners and etiquette. She is one of the more poised and composed companions, despite also being one of the youngest.
- The Quiet One: In comparison to Adric and Tegan, which is admittedly not saying much, but Nyssa was never one to raise her voice unless necessary.
- The Reliable One: Stoic, quiet and capable, she didn't get involved in squabbles and got on with her duties on the sidelines.
- The Stoic: It's implied on the show and then confirmed outright in the expanded universe to be why she rarely lets the pain of losing her father and home planet show.
- Team Mom: Say what you will about three companions being too many, The Doctor would never have been able to wrangle the volatile Tegan and Adric on his own. Nyssa was always calm, compassionate and the voice of reason, pushing for others to feel heard and usually acting as the team mediator. Most noticeable when she consoles Adric after his argument with The Doctor in "Earthshock", coming to him with the very motherly line "now, it's all starting to get a little bit silly, isn't it?". It works, even though she and Adric are the same age.
- Teen Genius: Her skill and knowledge with various scientific and technological concepts would be impressive in a woman twice her age, let alone a teenager.
- Tomboy and Girly Girl: The girly girl to Tegan's Tomboy.
- Tomboy with a Girly Streak: Wore make-up, feminine styled hair, and skirts, in addition to being a practical intellectual and adventurer.
- Wise Beyond Their Years: Nyssa was extremely calm, logical and level-headed, usually coming to grips with The Doctor's technical exposition faster than her fellow companions, possessing extremely advanced scientific knowledge and generally serving as a calming, stabilising influence, despite still being a teenager.
- Written-In Absence: An unfortunate side-effect of being added to the cast at a relatively late stage, many of the scripts following Nyssa's introduction had relatively little for her to do. The most notable example of this was the serial "Kinda", where she inexplicably faints and naps off-screen in the TARDIS for the remainder of the serial (as Sarah Sutton's contract did not cover every episode of the season).
- You Can't Go Home Again: Traken is destroyed by the universal entropy caused by the Master's meddling in "Logopolis".
Tegan Jovanka (Fourth, Fifth and Thirteenth Doctors)

Tegan: Groggy, sore, and bad-tempered.
Fifth Doctor: Almost your old self, then!
A brash Australian, inadvertently kidnapped from 1981 just as she was about to start a new job as a flight attendant. Self-described as "just a mouth on legs", Tegan was always the first to voice complaints about the latest mess the Doctor had landed them in and spent most of her time in the TARDIS epitomizing the Sarcastic Devotee, but she also had a lot of faith in him and a great affection for her fellow travelling companions, especially Nyssa. Despite her complaining, Tegan never hesitated to help others in need, particularly the oppressed and down-trodden, and she was never shy about confronting the bad guys, even physically attacking the Master in her first appearance. Created to help make the show more popular in Australia, and theorized by Peter Davison to have been a scheme by John Nathan-Turner to get free flights from Qantas.
One of a very few companions seen to pilot the TARDIS, albeit not very well. Janet Fielding was the longest-serving companion of the original series run, if you count by time elapsed between first and last regular appearance instead of by number of episodes or individual stories. Counting her brief appearance as a hallucination in "The Caves of Androzani"), she also appears in every single Peter Davison story except "Planet of Fire".
- Action Survivor: Downplayed, but even from her first appearance Tegan was never one to stand around and scream while the Monster of the Week advanced on her. She physically attacked the Master at least twice, including throwing a knife at his head (not that it helped), and wasn't afraid to fight back when cornered against Cybermen and Terileptils.
- Ambiguously Bi: "Farewell, Sarah Jane" refers to "a nice couple from Australia, Tegan and Nyssa", but it's not clear if they're actually a couple. According to "The Power of the Doctor" she's "seen off two husbands", while the Short Trips story "Good Companions" has her married to Dr William Haybourne until he dies of old age in the 2030s.
- And I Must Scream: Her second time hosting the Mara.
- Animated Tattoo: The Mark of the Mara, though it was only temporary.
- Barrier Maiden: In the mini-episode to celebrate the rerelease of the Season 20 boxset, it's revealed she's still hosting the Mara, who every now and then keeps tempting her with the hope of a reunion with Nyssa and the good days of traveling. Tegan's only answer is to remind the monster it's powerless without her, endure the nightmare and the offer, and smack it back into its box inside her head.
- Book Dumb: Subverted. Tegan was as well-educated as one would expect of a late-20th Century human, and her knowledge of her local time period and relative history occasionally proved useful in her adventures. But she was flying around in the TARDIS with the Doctor, Adric, Nyssa and Turlough — all of whom were aliens from very advanced species, who often managed to show her up due to sheer experience.
- Break the Haughty: Her second time hosting the Mara in her head doesn't leave her asleep through the ordeal, and she experiences it as a horrific And I Must Scream situation. She ends up with a disturbingly realistic trauma, crying and shaking while all the Doctor can do is hold her. After several years in the TARDIS, the violence and death that is an unfortunate inevitability in the Doctor's travels eventually became too much for her, causing her to Opt Out. Later expanded universe stories that follow up on her post-Doctor life suggest that she suffered from a form of PTSD.
- The Bus Came Back: After her departure prior to Fifth's regeneration, Tegan shows up in Thirteenth's final story alongside Ace.
- The Cat Came Back: The Doctor eventually got her back to Heathrow Airport and left her there so she could finally start work as an air stewardess. She returns in the next season, having been fired in very short order and then managed to find the TARDIS again. Somehow.
- Catchphrase: Her U-Rated profanity "Rabbits!" is universally remembered as such. (Though of course, the evils of rabbits are Serious Business to an Australian.) Despite this, she only uttered it twice onscreen, in "Logopolis" and "Frontios", though she makes up for it by using it much more regularly in other media.
- Contrasting Replacement Character: Whereas Romana was alien, patient and erudite, Tegan was down-to-earth, bossy and abrasive.
- A Day in the Limelight: "Kinda" and "Snakedance" focus on her, specifically on her experiences being possessed by the Mara. (Although in terms of what the characters actually get to do, she's almost as sidelined in the first one as Nyssa, who's asleep for the entire plot.)
- Deadpan Snarker: There's a reason she's called "the mouth on legs".Tegan: Is that supposed to be Heathrow?Adric: It is.Tegan: Well, they've certainly let the grass grow since I was last there.Adric: Well, actually, they haven't built the airport yet. We're about three hundred years early.Tegan: That's great! Perhaps I can go out, file a claim on the land. When they get round to inventing the aircraft, I'll make a fortune.
- Demonic Possession: Has the dubious honour of playing host to the Mara both times it shows up.
- Department of Redundancy Department:Tegan: How do we find the index file? Of course, if we had an index file, we could look it up in the index file under 'index file'! What am I saying?!
- '80s Hair: Originally a perm underneath a hairpiece with another perm and then a red wash put through it because John Nathan-Turner thought her hair made her look too much like Adric. Before filming began on Season 20, Janet Fielding cut her hair very short because she hated the original look. "A Fix With Sontarans" later shows her with the most 80s hair imaginable, a short, frosted blowout with a longer, dead straight piece rather obviously clipped into the back. It is the second-most horrifying aspect of that episode.
- Evil Sounds Deep: When she's possessed by the Mara. For some reason, it also makes her sound British.
- Expy According to Janet Fielding in "Girls! Girls! Girls", she always pictured Tegan as the Lucy van Pelt of the TARDIS group.
- Ignored Enamoured Underling: Much of her characterisation is hard to interpret in any way other than her having an unrequited love for the Fifth Doctor that couldn't be explicitly stated because of the No Hugging, No Kissing rule. Apart from the fans who think that the unrequited love was for Nyssa instead.
- Last Episode, New Character: She debuts in the Fourth Doctor's last serial.
- Limited Wardrobe: Keeps wearing her mauve cabin crew uniform throughout Season Nineteen, even when given the option of changing outfits in "Castrovalva". Her reasoning for this is that when the Doctor eventually gets her back to Heathrow, she will be able to leave The TARDIS and go straight into her job before it takes off into another adventure again.
- Her Season 20 outfit of a white, corseted boob tube with matching shorts and cardigan received no such explanation. She rotates out a couple of different outfits for Season 21.
- Line-of-Sight Name: How the character was named. John Nathan-Turner was either going to choose Tegan, for an Australian friend's niece, or Jovanka, after the wife of Yugoslavian president Josip Broz Tito. Script-editor Christopher H. Bidmead read Tegan as the first name and Jovanka as the last name. The rest, as they say, is history.
- Never Mess with Granny: In "The Power of the Doctor", Tegan is in her 60s and manages to completely disable the Master's entire Cyberman army (with a little assistance from a psychic hologram of the Doctor). Age hasn't mellowed her even slightly, as she wastes no time in giving the Doctor a dressing down and leaves her with very little choice when she decides she wants to see inside the TARDIS again. She is also the one that ultimately freezes and blows up Ashad in Adric's name. An additional mini-episode shows she regularly battles the Mara's remnant in her mind, and the monster has yet to make the slightest bit of leeway out.
- No-Sell: She manages to shut an Eternal, an ancient, massively powerful psychic being, out of her mind in "Enlightenment", just because he was annoying her too much.
- Odd Friendship: With Nyssa, who's quiet, scientifically-minded, and always willing to help out — the exact opposite of Tegan.
- Opt Out: After several years of travelling with the Doctor and witnessing just as many violent murders as intergalactic wonders, the deaths of "a lot of good people" is the last straw for Tegan.Tegan: My Aunt Vanessa said, when I became an air stewardess, "if you stop enjoying it, give it up."Doctor: Tegan-Tegan: It's stopped being fun, Doctor!
- Plucky Girl: Up to a point. Tegan gets kidnapped across space and time, her aunt gets murdered, she becomes possessed by the Mara twice and loses her friend Adric, all on top of the usual death and disaster that happens while travelling with the Doctor, but she always bounces back with a smile and a quip. It does all start to wear on her, though, and without the comforting presence of Nyssa around, she eventually sees one violent death too many and decides to leave Team TARDIS for good.
- Properly Paranoid: Even after Nyssa and the Doctor have accepted Turlough on board and he makes a concerted effort to earn her trust, Tegan doesn't stop believing he's up to something. Naturally, she's proven right.
- Reluctant Hero: For her first few adventures, anyway. Tegan stumbled into the TARDIS and got swept away to Logopolis completely by accident, and all she really wanted was to get home and start her job as an air stewardess. The TARDIS being the TARDIS, of course, means she has to wait quite a while to get there. She eventually comes to appreciate and even enjoy her travels, and eagerly rejoins the Doctor and Nyssa again in Amsterdam in "Arc of Infinity", though the Doctor himself is a little nonplussed by this.
- Sarcastic Devotee: Tegan is probably the best-known example of this trope in the original series, and in many ways is a precursor for Donna Noble in the revival. She's usually snarking at someone, either the Doctor, Adric (and later Turlough), or the Monster of the Week.
- Sexy Stewardess: Even outright refuses to change into a more normal outfit during her first proper adventure.
- Snark-to-Snark Combat: Though she had many arguments with Adric, he generally came off as more bratty and childish, and Tegan usually gained the upper hand. Turlough, on the other hand, really gave her a run for her money.
- Sour Supporter: Tegan would complain to the Doctor and nitpick his plans and actions until she was blue in the face, but she always stuck by him and never once lost her faith in his ability to save the day.
- The Team Normal: Tegan was the Doctor's first human companion (from Earth, anyway) since Sarah Jane, and unlike Nyssa and Adric she had no special alien abilities to bring to the table. This didn't stop her from killing a Cyberman or throwing a knife at the Master's head.
- Token Human: The only Earthling among the Fifth Doctor’s many companions until Peri, who replaced her.
- Tomboy and Girly Girl: The tomboy to Nyssa's girly girl.
- Took a Level in Badass:
- She's a Non-Action Snarker for much of her initial run. But "Earthshock" finally sees her changing out of her stewardess gear and into a combat outfit, leaping into action, and shooting a Cyberman to death with its own gun.
- It's a very quick and easy-to-miss moment, but in "The King's Demons", Tegan doesn't hesitate to throw a knife at the Master. Specifically, at his head.
- By the time of her reappearance in "The Power of the Doctor", Tegan is in her 60s and has absolutely no problem attacking Cybermen with a machine gun or scaling through the internal ducts of UNIT headquarters.
- Tsundere: The deredere being nearly vestigial.
- Unfazed Everyman: Her first reaction on seeing the inside of the TARDIS isn't shock, or even curiosity — but the immediate urge to go seek out the pilot and tell him he's a rubbish driver.
- Vitriolic Best Buds:
- With Adric. They seem to care as much as they bicker, especially when one of them gets captured. And she was devastated by Adric's death in Earthshock.
- Also with Turlough. To start with, she distrusts him (with good reason) and he looks down on her, and they argue constantly. But they also protect and rescue each other on multiple occasions, and when she leaves, Tegan is just as emotional saying goodbye to him as the Doctor, and Turlough is similarly affected.
- Weirdness Magnet: It starts with her being accidentally kidnapped by the Doctor and Adric after stumbling into the TARDIS, and things only get worse for her from there. She even manages to somehow find the TARDIS again, in Amsterdam of all places, only a few months after she left the first time.
