It’s been official since January that Peter Capaldi is leaving Doctor Who, and that his last episode will air at Christmas of this year. More recently it’s been announced that he would be facing the 1966 Cybermen this season — the strange headlamp-and-cloth-face-mask version we saw in their very first appearance, which happened also to be William Hartnell’s very last (consecutive) appearance as the First Doctor.

This got me thinking: is it possible that the Twelfth Doctor would go out the way the First Doctor did? It’s the sort of thing a big fan of the show like Capaldi might request, and while he’ll definitely appear in the Christmas special, it could very well be a flashback.

I know, it sounds far-fetched to me too — anticlimactically repetitive, for a start, and convoluted even for Moffat. But it got me thinking about the different ways the Doctors have regenerated, and speculating about what we might expect this time. I thought it might be interesting to compare the enemies involved in regeneration stories, the catalysts that have helped the process along, and the causes of “death.”

As a bonus, I’ll offer a short take on the personality shifts between incarnations, according to my theory (I don’t remember if I came up with it, but I like it) that even within the story the Doctor is subconsciously “recasting” himself to correct any flaws he might perceive in his ending persona (whether we agree that they’re flaws or not) and become the new person he believes he might need to be.

First Doctor

Enemy: The Cybermen
Catalyst: The TARDIS
Cause: Exhaustion
Quote: “This old body of mine is wearing a bit thin.”

Though the early Cybermen were all about draining energy, there’s no explicit indication that they were draining it from the Doctor himself. To all appearances, he’s simply aged his first body as far as it can go, and it’s time to renew it. In the next story, his new self comments that this process is “part of the TARDIS,” suggesting that access to his ship is essential for regeneration to succeed. Indeed, there will be only three regenerations that don’t happen in or near the TARDIS, and all three of them have some other catalyst involved. This is never again explicitly stated, but we could assume that wherever I’ve noted the catalyst as “none,” the TARDIS is still playing that role.

This incarnation could be physically infirm and lacking in warmth; he becomes a younger, more charming man whose signature tactic is to run.

Second Doctor

Enemy: The War Lords
Catalyst: The Time Lords
Cause: Induction
Quote: “The time has come for you to change your appearance, Doctor, and begin your exile.”

So far the Second Doctor has been the only one to have regenerated while in perfect health. He is in a sense executed by the Time Lords for becoming too involved in the affairs of worlds outside Gallifrey. We might imagine this experience to be as traumatic as an execution, but little onscreen suggests it’s physically painful, as opposed to merely emotionally unpleasant. Still, though the enemy of this story is technically the War Lords (themselves an organization or species we might describe as degraded, inverted Time Lords), the Time Lords themselves are the cause of the actual regeneration, and might just as well be considered eleventh-hour antagonists.

Though demonstrably brilliant and capable, this incarnation sometimes found it difficult to command respect at first glance, and was not especially imposing physically. He becomes a more patrician, authoritative Doctor with a mastery of multiple martial arts.

Third Doctor

Enemy: The Giant Spiders of Metebelis III
Catalyst: Cho-Je
Cause: Radiation
Quote: “All the cells of his body have been devastated by the Metebelis crystals, but you forget, he is a Time Lord. I will give the process a little push and the cells will regenerate.”

The same alien radiation emitted by the blue crystals of Metebelis III that caused ordinary spiders from Earth to grow giant in size and intellectual capacity proved deadly in full doses, not just to their monarch the Great One, but also to the Doctor. Earlier in the same story, he takes a nearly-lethal spike of spidery lightning which knocks him almost comatose until Sarah Jane brings him medical equipment from the TARDIS, so he’s already poorly. Though he has his TARDIS nearby for the regeneration, he needs a little extra help from a fellow Time Lord.

While he was much more likely to rebuke authority figures than he’s given credit for, this incarnation developed a respect for human institutions and etiquette that probably constrained him a bit. His next would almost immediately display a detached, anarchic streak and a much healthier sense of humor about himself and the rest of the universe.

Fourth Doctor

Enemy: The Master
Catalyst: The Watcher
Cause: Trauma
Quote: “It’s the end. But the moment has been prepared for.”

One of the most violent regenerations to date, and the only one the Master can be said to be directly involved in. On the beam of a radio telescope, the Fourth Doctor fights the Master, who deliberately tilts the dish so that the Doctor slides off, dangles by a cable, loses his grip, and plunges to the ground. This is a family show, so he’s externally unscathed, but there’s no doubt he’s had it. The TARDIS is a good distance away, but a catalyst is at hand: a sort of plaster-of-Paris-covered mime who merges with him to become the Fifth Doctor.

We might think of the Watcher as an autonomous projection of the Doctor, much as Cho-Je was an autonomous projection of the K’anpo Rimpoche, the Doctor’s former teacher. Maybe that’s where the Doctor got the idea to try a less polished version of the same trick. We don’t see clear evidence that summoning the Watcher was a conscious choice, but there’s plenty to suggest the Doctor might be expecting disaster. He’s uncharacteristically somber from the start, intoning gloomily about entropy — and why take a sudden urge to repair the chameleon circuit? Perhaps he knows something terrible is coming, even suspects that the Master may not have died on Traken, and creates the Watcher as a form of insurance? Which means we might also think of the Watcher as a horcrux.

But this is 1981, so JK Rowling is only 16, and anyway it’s a little creepy to think of the Doctor as a lich with a phylactery, isn’t it? Still.

This incarnation of the Doctor was getting a little untouchable by the end, a little too sure of himself, a little arrogant perhaps, and maybe that was making him a little hard to be around. Next time, maybe he’d try to be a little more human, a little more approachable, a little more vulnerable. Given his hobbies, maybe not really the best move.

Fifth Doctor

Enemy: Sharaz Jek, Morgus, and all the other would-be profiteers and exploiters of Androzani Minor
Catalyst: none
Cause: Toxaemia
Quote: “Cramp is the second stage. First a rash, then spasms, finally slow paralysis of the thoracic spinal nerve and then TDP. Thermal death point. It’s called Spectrox toxaemia. I’ve seen dozens die from it.”

Toxaemia — blood poisoning brought on by an infection or a toxic substance — is probably the most gruesome regeneration cause we’ve seen so far. First of all, it’s a much more down-and-dirty biological sort of affliction than radiation or the trauma of falling from a great height. But eventually we learn that while the refined form of spectrox (the toxic substance in question) is a life-extending drug probably inspired by Dune‘s melange, its original form is literally bat guano. That is to say, the Doctor and Peri spend the entire story slowly dying because they fell into a pit of bat shit. Can you imagine the Tumblr anguish if they’d done that to David Tennant?

Enemy-wise, it’s hard to blame any of the local warlords, venal bureaucrats, gunrunners, and other assorted criminals for this situation; our heroes step in poop before they meet anyone else on the planet and in fact would have died if they hadn’t gotten some crucial advice about the antitoxin. Well, Peri would have died; the Doctor would have survived, and that would have been awkward. Though less whiny.

This incarnation wasn’t a total wimp, but he was in a lot of situations where he could have benefited from being just a little tougher. Maybe after an adventure in which he was nearly shot to death by a firing squad and had to crash-land a ship and crawl into an airless cave to milk a queen bat, his dying self thought back to that dashing but ruthless Gallifreyan Commander Maxil and wished he’d been a little more like that….

Sixth Doctor

Enemy: The Rani
Catalyst: none
Cause: Trauma
Quote: “Yes, it exploded and threw you to the floor. Me, too. Knocked us both cold. When I came round you looked like this.”

It’s not entirely clear what causes the Sixth Doctor to regenerate. The relevant quote here is from the Rani, an amoral Time Lord disguised as the Doctor’s companion Mel. The “it” that “exploded” is an experiment that the Rani is making up as an explanation for an amnesiac Doctor. We know that in truth she’s brought down the TARDIS herself with some sort of energy bolts that knocked it out of the vortex, with the aim of getting the Doctor to help her complete her latest science project. So whatever the energy bolts are, they weren’t supposed to hurt him or cause him to regenerate, and after all they leave Mel unconscious but unconcussed. So we have to assume that either some part of the TARDIS does explode and injure him severely and Mel superficially, or — as goes the usual wisdom — he happened to hit his head hard enough to “kill” him. Perhaps the Rani’s energy bolts happened to catch him off-balance on his exercise bike.

This incarnation was abrasive, conceited, pretentious, and often downright nasty and abusive. This made it easy to overlook that — after his regeneration settled down — he was also protective, noble, outgoing, literate, and unafraid to get his hands dirty. There wasn’t a subtle bone in his body, and maybe that’s what drove him toward a regeneration that, like his first, brought him a personality with charm, a smooth tongue, and a deceptively unthreatening appearance.

Seventh Doctor

Enemy: The Master, a trigger-happy street gang, and San Francisco surgical procedures just before the year 2000
Catalyst: A thunderstorm?
Cause: Trauma
Quote: “And here we have an electro-physiology being performed by one of our senior cardiologists, Doctor Holloway, who will insert a micro-surgical probe into the patient’s artery, then search out the short-circuiting part causing the fibrillation, and just so that you know your money is being well spent, we’ll blast it with lasers.”

In which the famously ten-steps-ahead chess-playing master strategist Doctor dashes out of the TARDIS without checking a single scanner or instrument, right into a random San Francisco gangland shooting. Adding injury to insult, the bullets aren’t quite enough to kill him — instead, he is operated on by his companion-to-be, who skipped Alien Physiology in med school, and so has no idea how Time Lord physiology differs from the humans she’s used to. Rather than saving him, her procedure finishes him off. No wonder people are afraid of hospitals. Here the Master mainly just benefits from the situation rather than causing it. This is perhaps the first of the delayed regenerations, though rather than walking around and casually chatting with his former companions as has become customary since 2005, the Doctor is apparently dead for hours. The TARDIS isn’t nearby to help, and maybe this is partly why it takes so long. It’s not clear whether the coincidental thunderstorm plays any catalytic role, or if it’s just a clumsy Frankenstein allusion.

This incarnation, though perhaps resembling your most huggable uncle, was probably not going to have the chance to smooch too many mildly attractive incompetent surgeons. Maybe subconsciously he felt it was time to try being youthful and handsome and spontaneous again.

Eighth Doctor

Enemy: The Daleks
Catalyst: A magic potion!
Cause: Trauma
Quote: “Our elixir can trigger your regeneration, bring you back. Time Lord science is elevated here on Karn. The change doesn’t have to be random. Fat or thin, young or old, man or woman?”

Though the Daleks don’t make an appearance here, they’re the antagonist in the Time War, and even if the Time Lords are equally to blame, it’s clear what side the Doctor ends up taking. Like the Fourth Doctor, the Eighth has crashed to the ground hard and is all messed up inside. The TARDIS is somewhere in the wreckage, but we don’t know how far — maybe even farther away than it was in “Logopolis.” Fortunately the Sisterhood of Karn — a planet that might be the most crashed-on in the whole galaxy — have some potions ready to go, and they’ve been tight with the Time Lords for ages so they know what they’re doing.

No mystery at all what transition the Doctor mulls here. He gets to make a conscious choice to become a fighter, not a lover. Why that fighter is in the form of John Hurt and not, say, Tom Hardy or Daniel Craig or the Rock is a little mysterious; even Christopher Eccleston seems like more of a “fighter,” and of course we know it very nearly was him after all. But maybe there’s only so far the Doctor can go in the direction of badassedness, which is why he’s not the Warrior but the War Doctor.

War Doctor

Enemy: The Daleks
Catalyst: none
Cause: Exhaustion
Quote: “Oh yes, of course. I suppose it makes sense. Wearing a bit thin. I hope the ears are a bit less conspicuous this time.”

Here again, no Daleks are shooting at him, but what must have been centuries (as much as one can reckon time in the midst of a Time War) of fighting them must have been what wore him out. Still, he isn’t quite expecting to regenerate, but once it starts he acts as though it were an obvious next step. The line “wearing a bit thin” of course echoes his first regeneration, supporting the idea that the cause in both cases is the same: a “natural” death of “old age.” Part of what “makes sense” is that now the war is over and he no longer needs to be the War Doctor. Interestingly, if this had been Eccleston, there would have been no regeneration scene.

This incarnation had a heavy burden, and we have to assume he didn’t have a lot of time to explore the universe, flip through tabloids, visit past Earth history, or eat chips. He also had started to be a different kind of Doctor — younger, more dashing, less intellectual, more emotional, and maybe he wanted to get back on that track. Or maybe after so long looking like he didn’t belong in any particular time or place, he thought it might be good to be the kind of man who could blend in on the streets of 21st century London and just relax.

Ninth Doctor

Enemy: The Daleks
Catalyst: none
Cause: Radiation
Quote: “I absorbed all the energy of the Time Vortex, and no one’s meant to do that. Every cell in my body’s dying.”

Radiation hasn’t taken out a Doctor since 1974, so it’s due to come back into fashion. It’s a nice clean cause of death, invisible and almost magic. The idea that the Doctor can kiss it out of someone else like he’s sucking venom from a rattlesnake bite is a little far-fetched, but this is Doctor Who, so why not. The language he uses here is almost certainly a deliberate reference to that previous regeneration.

Again, the Ninth Doctor isn’t bad-looking, but right now he’s Rose’s fun uncle, and if he’s going to fall in love with her — which he does, come on, of course he does — he’ll need to be Casanova, but with better hair.

Handy

Enemy: The Daleks
Catalyst: Donna
Cause: Trauma
Quote: “I’m unique. Never been another like me. Because all that regeneration energy went into the hand. Look at my hand. I love that hand. But then you touched it. Wham! Shush. Instantaneous biological metacrisis. I grew out of you. Still, could be worse.”

I bring up Handy for two reasons only. One, he arguably counts as an actual regeneration, as irritating as that idea is. And two, if we are pursuing this theory that regenerations produce a new incarnation that “corrects” the flaws of the previous one, it’s possible that at this point in time the Tenth Doctor thinks he is flawless.

Okay, three reasons: the quote above is preceded by an even better one, to wit, Donna speculating, “Is that what Time Lords do? Lop a bit off, grow another one? You’re like worms.”

Tenth Doctor

Enemy: The Time Lords
Catalyst: none
Cause: Radiation
Quote: “All the excess radiation gets vented inside there. Vinvocci glass contains it. All five hundred thousand rads, about to flood that thing.”

Technically, the Time Lords are pulling all the strings, though probably some of the blame goes to the Naismiths. Though, really, if I were trying to pin down the root culprit of these regenerations rather than the antagonist du jour, I’d probably have to point to — not Wilf, but the Vinvocci and their completely unsafe, poorly designed radiation death trap technology. What’s wrong with those idiots and their “opening one cabinet locks the other” industrial design? Do they not realize that we just had a radiation regeneration last time (Handy notwithstanding)? While we’re on the subject of the absurd, how is it that the Tenth Doctor can survive a catastrophic fall but the Fourth and the Eighth can’t? He must have decided enough trauma was enough and did some intense body modification as the War Doctor, which might also explain his extraordinary resistance to electricity and extreme temperatures in “Evolution of the Daleks” and “42” respectively.

This incarnation was a bit too romantic — it compromised his judgment, broke his heart, hooked him up with a monarch, and cost him at least one companion who’d hoped for more from him than he could give. Maybe the next him could be slightly goofier, have sillier taste in clothes, and be a little less inclined to get involved with his female companions (historical celebrities would still be on the menu, though). In hindsight, though, he ought to have known this attempt would fail, considering he’d already met his wife.

Eleventh Doctor

Enemy: The Daleks, and any other enemies who haven’t gotten bored and left
Catalyst: The Time Lords
Cause: Exhaustion / induction
Quote: “Yes, I’m dying. You’ve been trying to kill me for centuries, and here I am, dying of old age. If you want something done, do it yourself.”

A bit of a special case, considering it was supposed to be the last one. Old age has, for only the third time in the Doctor’s lives, come to claim him when none of his massed enemies could close the deal, and so it’s what I’m calling exhaustion that kills him. But since the process would not be happening at all without a new regeneration cycle being sent through Amy’s Crack by the Time Lords, like some kind of extension on his cosmic taxes, the regeneration itself could be what I’m calling induced. As with the last few times, dying is now so comfortable for the Doctor that he can stroll around and chat with his companions for as long as he wants to, kind of taking a lot of the drama out of the whole affair and making it feel a bit like an awards show. It’s also the second instance of the “reset,” where any visible wounds or gray hairs or liver spots magically buff away, a bit like sprucing oneself up for that awards show.

This incarnation was still just a bit too dangerously attractive, only this time to slightly older women, self-described “psychopaths” with archaeology degrees or Dalek eyestalks coming out of their heads. Once and for all, maybe he would try to nip this thing in the bud and take it all back to where he began: a no-nonsense older man with a dangerous side, a lack of patience for silly humans, but underneath it all a current of warmth for his favorites of that species. He could come full circle and start it all over again, older and wiser. As long as he could avoid running into any old-school Mondasian Cybermen, maybe he could live forever….

And the awards go to…

Deadliest Enemy: The Daleks

It’s no surprise that the Doctor’s deadliest enemy, in terms of ushering in his regenerations, is his oldest (if you don’t count the primitive Earthlings of “100,000 B.C.”). Though they’ve rarely been the immediate cause of the regenerations (the only exception being Handy, who owes his existence to a would-be extermination bolt), they’ve been heavily involved in the conflicts that have led up to five of them. It’s interesting, however, that the runners-up are the Doctor’s own people: counting the Master and the Rani, Time Lords have taken four of the Doctor’s lives, more than they’ve helped to save.

Most Helpful Catalyst: The TARDIS

There should be an asterisk next to this one, since as mentioned above, the idea that regeneration is “part of the TARDIS” is never mentioned again after “Power of the Daleks.” So we can only assume that in the cases where no other catalyst is present, the TARDIS is taking care of the Time Lord it stole. But it’s a reasonable assumption for five regenerations and a stated fact for a sixth. The Time Lords themselves take a silver medal again, helping with four regenerations, if we count the Watcher (who, after all, “was the Doctor all the time” if Nyssa’s intuition is to be trusted).

Most Common Cause: Trauma

This is the biggest surprise of this exercise for me. I’d expected one of the more family-friendly causes of death to win out. If you group exhaustion, induction, and good old invisible radiation together, I suppose they still do, but individually they split the vote such that traumatic deaths — falling, being shot, and massive head injuries — squeak into first place with five (thanks once again to Handy). This suggests it’s entirely possible that the Twelfth Doctor might end up having something pretty scary and awful happen to him after all…though surely not at Christmas.

Sources
TRANSCRIPTS are thanks to chakoteya.net. One of the best Doctor Who resources on the web.
The IMAGE was found at: http://www.bbc.co.uk/blogs/doctorwho/entries/adff0629-5ce5-4a0e-b81a-69693d489745