Over the last 62 years, Doctor Who has been a lot of different TV shows, and the Doctor has been a lot of different characters, in more ways than one. There are common strands: cleverness mixed with tomfoolery mixed with one hell of an ego, an idiosyncratic dress sense, and a tendency towards big noses and Scottish accents. But each Doctor has their very own distinct flavour, and in each Doctors era, there is one story that captures the essence of the era.In tracking down those stories, were going to avoid regeneration stories at either end of the Time Lord life cycle if possible, because this isnt about how the Doctors are introduced or summarise themselves at the end. It is about that one story that shows who a Doctor is.The First Doctor The Dalek Invasion of Earth (1964)Anyone who writes Doctor Who for any length of time will eventually have the quite stupid thought What if we finally did the Doctors origin story?Andrew Cartmel thought he could do it with his great unrealised Masterplan. Moffat had a couple of goes, with both Claras visit to the Doctors childhood in Listen, and the somewhat messy, never quite adequately explained Hybrid plotline. And of course, there is the always-to-be-relitigated Timeless Child reveal under Chibnall. But the Doctors real origin story was already told in 1964.Doctor Who, starring William Hartnell, had been around for about a year. In the first episode he assumed the name The Doctor when Ian Chesterton refers to him as such and he likes the sound of it. The TARDIS gets stuck as a police box just because.However, the hero known as the Doctor is nowhere to be found. He kidnaps schoolteachers, attempts to bludgeon cavemen to death from behind, sabotages his own TARDIS so he can look around an alien planet, then riles its pacifist inhabitants into fighting a war so he can fix it again. The early Doctor Who stories are about the TARDIS crew arriving somewhere, getting into a scrape, getting out of it again and if some heroism happens along the way it is strictly a by-product.Until this story. When someone asks if the Daleks dare to meddle with the forces of creation, and the Doctor says They dare! And we must dare to stop them! it is our first glimpse of the Doctor of legend, a person who travels through space and time to willingly put themselves between monsters and people who need saving from monsters.The Second Doctor The Tomb of the Cybermen (1967)By the time of the Second Doctor, played by Patrick Troughton, he was well into the swing of fighting monsters. This was the era that codified the base under siege storyline while offering a conveyor belt of monsters.Troughton also had a quality that, frankly, new Doctor Who could stand to learn from. He was a Doctor who didnt mind being underestimated. Where every other Doctor wanted to be Sherlock Holmes, he was happy to be a Columbo, using flattery and modesty to disarm the megalomaniac until he could turn the tables.While the title might lead you to believe that the Cybermen are the lead villain of this story, the truth is the real baddies are Miss Kaftan and Eric Klieg, representing the Brotherhood of Logicians. The Brotherhood of Logicians is a secret society of technocrats who believe that their great intellect entitles them to rule over the human race (make your own satirical observations in the comments). That total confidence in their own intellectual superiority makes them absolutely perfect Second Doctor fodder.The Third Doctor The Claws of Axos (1971)Choosing the definitive Third Doctor story is difficult because it is an era with so many complex moving parts. It marked a temporary shift away from TARDIS-destination-of-the-week stories to Avengers (Steed and Peel, not Marvel)-style adventures with back-up from a global paramilitary organisation with a cool-sounding acronym. It also introduced a new enemy for the Doctor in the form of the goatee-loving Master.Join our mailing listGet the best of Den of Geek delivered right to your inbox!The Claws of Axos brings us the full Third Doctor toy box. The Doctor is in full UNIT employee mode, doing what he does best, being incredibly cross about it while having to argue with exactly the sort of bureaucrats he normally gets to ignore. There is an alien visitation that introduces itself as friendly but has a similar motive, and of course, those aliens are allied with the Master, who seeks to use the aliens for his own agenda.The outcome of this deal is so predictable that, with hindsight, you may be forgiven for thinking it was the Masters idea in the first place: The aliens turn on him, forcing the Doctor and the Master to work together to defeat the threat (he just wants attention!).It is frankly, everything you want from a Third Doctor story in one neat little box.The Fourth Doctor Genesis of the Daleks (1975)If Doctor Who had ended with Tom Bakers tenure, it would still be considered a classic series that had a pretty good run. The show evolved and had the sort of peaks and troughs of quality that you would expect for any programme that ran for seven years.Yet if you want the quintessential Fourth Doctor story, you need only look at that Doctors fourth story. It stands as a pretty good flagbearer for Doctor Who as a whole, even though it is that rare thing: a story without the TARDIS.Genesis of the Daleks, in many ways, has the perfect Doctor Who premise. It addresses the first question everyone asks of any time traveller, let alone the most do-gooding time traveller of them all. Why dont you just kill Hitler? (In case the metaphor of screeching, purity-obsessed tin-pots whose arms are stuck in a permanent sieg heil was too subtle for you, this story puts the Daleks creators in straight-up Gestapo uniforms.)It gives Baker room to flex every muscle he has. Say what you like about Nazis, but their arrogance and self-seriousness make them a great comic foil. Then, up against Davros in his first and greatest appearance, we see the Doctor grow serious as he grasps the sheer evil he is up against. And of course, there is the famous Have I the right? speech, where the Doctor has the opportunity to wipe out his enemy once and for all, and chooses not to.The Fifth Doctor Earthshock (1982)To younger fans (and by younger here I mean, People in their 30s and 40s) the Fifth Doctor has undergone a bit of a memetic evolution. Among the Doctors of the classic series, he was the Young One. We see him being chummy with David Tennant in the Children in Need Time Crash short, and hanging out with Tegan in The Power of the Doctor, and we watch Peter Davison in The Five-ish Doctors and he seems nice. A bit grumpy. Definitely not on a par with the likes of McCoy, Ecclestone and Capaldi when you need a Doctor to go dark.Yet what you forget about Tegan is that shes the companion who left the TARDIS in Resurrection of the Daleks because it was too fricking violent. If you watch this charming collection of times the Doctor has shot someone to death with a gun, the Fifth Doctor is better represented than most especially when you consider that in context, the Fourth Doctor is being framed in most of his scenes, and the Second Doctor is carrying a couple of big torches.The show had been on the air for 20 years, and a battle was raging over whether it was going to be dark and grown-up and edgy now its audience was growing up, or be a kids show forever. And one of the definitive strikes in that battle was Earthshock, where the show killed off Adric. Sure, Adric will never rank well in our Top 10 Least Annoying Doctor Who Companions listicle, but if Star Trek: The Next Generation murdered Wesley Crusher, itd still be considered a dark move.It set the tone that would eventually lead to the All-Time-Favourites-List regular, Caves of Androzani.The Sixth Doctor The Mark of the Rani (1985)Russell T Davies is credited with bringing a few innovations to Doctor Who: changing the episodes from 25 to 45 minutes each, amping up the flirtation between the Doctor and the Master, giving the Doctor a leather jacket instead of a clown-ish period costume covered in question marks. Which is all just a long way of saying poor Colin Baker.The Mark of the Rani is a story made of two 45-minute episodes, starring Colin Baker in a brightly coloured patchwork outfit (not the leather jacket he wanted to wear). In a terribly underserved era (Baker would go on to do much better in the Big Finish audios) this feels almost like a Davies-era historical. Almost.But the heart of the story is What if the Doctor had to fight an evil Time Lord who actually wanted to take over the world, rather than just flirt with him the whole time?This episode still suffers from all the flaws of its time, including post-2005 length episodes with pre-1988 level pacing, but it gives us a glimpse only a glimpse of what Baker might have done with better material.The Seventh Doctor Battlefield (1989)Just as Peter Davison can be unfairly pigeonholed as the nice one, Sylvester McCoys Doctor has a bit of an unearned reputation for being the dark, morally complex, grown-up Doctor of the classic era. Our image of the Seventh Doctor is as much defined by the Virgin Adventures with their deep lore, and stories about drug trafficking and war crimes, as it is by the 12 stories that aired on TV.The Doctor is just as much a funny man dangling from an umbrella over a cliff in Dragonfire as he is the manipulator who intentionally destroys Aces faith in him to defeat his adversary in The Curse of Fenric.And Battlefield shows us a nice halfway house between those two Seventh Doctors. It is a Doctor with friends, as we see him joyfully reunited with the Brigadier, not to mention his old car Betty. It is a Doctor with a past, but also a future (and while spin-off media have gone there a few times, were still dying to see the TV show give us The Doctor As Merlin). A Doctor who is capable of manipulating and plotting, but whose ultimate winning move is to appeal to his enemys mercy, as he does when he tells Jean Marshs Morgaine of the true horrors nuclear weapons will unleash.It is McCoys ability to master that scope, which he managed right from his audition, that puts him among the best actors in the role.The Eighth Doctor Night of the Doctor (2013)Yes, we said no regeneration stories, but you have to admit that were in a bit of a bind with this one. Of the two TV stories Paul McGann starred in as the Doctor, it isnt much of a contest. In The Movie, nobody is sure of themselves. Everyone, McGann included, is still finding their way. The Paul McGann who appears in The Night of the Doctor has held the title for as long as anyone (tied for nine years with McCoy), but while McCoy spent the time between the show being cancelled and his swan song in the movie in other roles, or on the convention circuit, McGann spent his off-screen hiatus starring in dozens of audio plays, getting to know the character better, refining his performance, and getting to do things with the character that frankly, the TV show would never let you get away with.From Bring me knitting to saying farewell by name to each of his audio drama companions, we see McGann bring the full range a Doctor Who actor is expected to deliver, with the weight of an actor who has waited longer than anyone for his final bow.The War Doctor The Day of the Doctor (2013)It was his one episode, come on, keep up.The Ninth Doctor Boom Town (2005)This isnt a best-of list. Boom Town is probably not anyones favourite. Its probably not anyones favourite Christopher Eccleston episode. But this is where we see the Ninth Doctor at his height. Hes got his TARDIS crew, Rose and Jack and even Mickey turning up to join in. Hes watched the last Dalek die, has The One Where Everybody Lives (The Empty Child/The Doctor Dances) under his belt, and is starting to seem like he might just be starting to heal from all that trauma hes carrying around. Honestly, wouldve been nice to get another season or two out of him at this point before finding what all that Bad Wolf stuff is about.But here is also where we find out who this Doctor is, and in the best possible way. Catch the villain right at the start of the episode, then make the Doctor sit down for dinner with them. This isnt a Doctor who will let you underestimate him. This isnt a Doctor who will ask if he has the right. Hes decided he does, and has done, over and over again by this point. This is a Doctor whos done terrible things and lived with them, and despite all of that still really wants to try and be the hero people think he is.The Tenth Doctor School Reunion (2006)This has been one of the hardest ones to pick, because the Tenth Doctor is always so completely The Tenth Doctor. Until David Tennant came along, on some level all Doctor actors were doing a Tom Baker impression. After Tennant, a bit of them was always doing a Tennant impression as well.So its fitting that the best showcase for Tennants Doctor introduces him to a companion of the Fourth. In this story we get the full Doctor Acting Range experience, from the Doctor cheerfully posing as a supply teacher, to the chilling delivery of I used to have so much mercy. Here we see the seeds of the Tenth Doctors ultimate arc. In The Runaway Bride, when Donna tells him I think you need someone to stop you, and in the Time Lord Victorious speech in The Waters of Mars the seeds of that journey are planted here when the Doctor is offered the chance to save everyone, if he only takes over the universe.And of course, the Tenth Doctors story is ultimately all about Rose Tyler, so seeing her realise her place as the latest in a long line, rather than the one and only, shines a big light on that relationship.The Eleventh Doctor A Good Man Goes to War (2011)Remember the Second Doctor? The Columbo in a line of Sherlock Holmeses? That man is long gone. Both the character and the TV show have been on a long journey since then, and in both the legend of who the Doctor is has grown. By this point, the Doctor barely even needs to outwit the enemy anymore. He just needs to tell them to look him up.This is where it peaks. Not at Trenzalore (a skirmish by your standards as the Great Intelligence points out), not in bringing back Gallifrey, but here. The stakes are not the planet or the universe, but the Doctors friend and her child, and the Doctor raises an army to get them back. This is the Doctor at the climax of the journey he started in The Dalek Invasion of Earth, truly believing his own hype as the Oncoming Storm.And Matt Smith, probably one of the most Doctor-ish of Doctor actors, is at his most Doctor-ish hair. Clowning and silly (Point a gun at me if it makes you feel better!), menacing (Telling the newly-crowned Colonel Runaway I want you to tell them your name.), hopping backwards and forwards through time to recruit anyone he needs, because they all owe him favours.Then he loses, and that paves the way for what comes next.The Twelfth Doctor The Wizards Apprentice/The Witchs Familiar (2015)The Doctor is back on the Dalek home planet of Skaro again, with a gun pointed right at baby Hitler (sorry, Davros). And yet, given that this two-parter is also a season premiere, it feels oddly routine as far as Nu Who Dalek episodes go. Which is why its such a good showcase of Capaldi.We see how this Doctor reacts to learning hes going to die, which to be fair, after He will knock four times and the exploding TARDIS arc from Series 5 and Trenzalore, is a pretty routine occurrence. This time rather than raging against the dying of the light, he throws a party. But thats not the reason why this is the story weve chosen to sum up Capaldis time as the Doctor.See, once again, Capaldi is one of those dark Doctors. Spends his first series wondering if hes a good person while making trolley problem decisions left and right. But this whole two-parter, this entire story, comes down to one decision. Davros tells the Doctor hes dying, and asks him to come and visit, and the Doctor agrees. Even though Davros is his worst enemy (sorry Missy). Even though Davros will probably kill him. The Doctor walks right into an obvious trap, and he does it because its the kind thing to do.However grumpy he gets, that is the thing that most defines this version of the Doctor one who has (mostly) got over his own hype, and now just wants to help.The Thirteenth Doctor Rosa (2018) Once again, we are not here to make a best-of list, but Rosa remains one of the best stories in Jodie Whittakers time in the TARDIS. It encapsulates a lot of what was best about her and Chibnalls era. It took us to a place and a time the show had not visited before, the segregation-era Deep South. It was unapologetic and unflinching in talking about social issues, and made an effort to educate about history in a way that the show perhaps hadnt done since Hartnells time.And yet, as happened a lot under Chibnall, muddled storytelling led to some pretty weird messaging, despite its noble goals. Things like the Doctor and Graham having to heroically take up seats in the whites-only part of the bus to ensure Rosa Parks would be asked to stand.Another thing you can see Chibnall doing throughout his run is trying to move the Doctor away from the grandstanding we see in A Good Man Goes to War, but again, that goal has mixed results when you combine it with the first time the character is played by a woman. It leads to a Doctor who, on more than one occasion, is willing to be a spectator when injustice happens, which just isnt the gig.The Fourteenth Doctor The GiggleOnce again weve broken our No regenerations episodes rule, but once again I think you can agree we have our reasons here. Wild Blue Yonder is an all-time great Doctor Who episode, but it doesnt get to the heart of who this version of the Doctor is as much as The Giggle. The finale of the 60th anniversary specials trilogy is almost like an exorcism. After The Star Beast showed us Russell T Davies triumphant return with exactly the sort of grounded-yet-fantastic season opener he excels at, followed by the minimalist, misanthropic and claustrophobic horror of Wild Blue Yonder, The Giggle is the embodiment of everything any fan on the internet complained about from 2005 to 2010. Camp villains doing musical numbers, completely-on-the-nose political commentary, the Doctor getting weepy about his sad backstory, an insane deus-ex-machina ending that raises more questions than it answers, Russell T Davies dances in front of his critics like Neil Patrick Harris in front of UNIT machine gun fire.This is what defines the Fourteenth Doctor the Tenth Doctor with the brakes well and truly off.The Fifteenth Doctor Space Babies (2024)Ncuti Gatwas time in the TARDIS is far from over. Maybe his incarnation of the Doctor will see a transformation as dramatic as Capaldis between Deep Breath and Twice Upon a Time. But his first full, non-Christmas special episode in the role provides a pretty strong mission statement. It puts the Doctor exactly where the Doctor most likes to be between some children and a monster. Then he does the thing the Doctor is best at finding the humanity in that monster.This episode shows us a Doctor who is more open than any of his predecessors, telling Ruby that his people are GONE! right from the start, but also adding that he is so glad to be alive. But what clinches it, what really shows us who this Doctor is, who the Doctor is, is the line Nobody grows up wrong.Thats Doctor Who, right there.