To be honest, I rather dislike reviewing the first part of two-part finales. Like 2014's "Dark Water"—and we all know how well that turned out—"World Enough and Time" is a long set-up of mysteries and crises that next week may or may not manage to resolve in a satisfactory way.

But, that being said, "World Enough and Time" is a pretty good set-up. What's more, as the first part of Steven Moffat's penultimate story as Doctor Who's showrunner, it manages to feel fresh and exciting, while functioning as a remarkably coherent greatest-hits tape for the Moffat age. Moffat revisits a lot of his favorite tropes and themes here, which made me feel downright nostalgic for the era about to end. Dare we hope this means there's been a method to the madness all along, and that Moffat is building up to tying a nice, thematically-consistent bow around his entire run?

Probably not, but it's pretty to think so. So let's take a look at this episode while revisiting some key themes of the seven-year Moffat era.

"She's the only person I've ever met who's even remotely like me."

As I mentioned last week, this year's season-long arc is the most satisfactory of Moffat's entire run, because it's grounded in character, not contrivance. Cracks in Time, Impossible Astronauts, Impossible Girls, Promised Lands, and Hybrids are all well and good, but they all followed the Russell T. Davies "Bad Wolf"/"Vote Saxon" model of dropping enigmatic teases throughout their respective seasons. They were taunting mysteries we weren't really meant to figure out, and their explanations—by the time they finally came—tended to be anti-climactic, incomprehensible, or both.

Moffat is doing something different in Season Ten. The Vault looked like it was going to be that kind of mystery, but its secrets were all surrendered by Episode Six. The ultimate questions of this season aren't about who or what is in the Vault, but who or what is in Missy, the Vault's occupant. Is she harboring an evil plan? Is she willing to, and capable of, change? Can she possibly be—could she ever possibly be—good?

In this second half of the season we've seen Missy inch closer to what seemed like genuine redemption. In "The Lie of the Land," she helped the Doctor figure out how to defeat the Monks, and demonstrated remorse for her countless victims. In "Empress of Mars," she rescued the Doctor and Bill instead of killing Nardole and making off with the TARDIS. In "The Eaters of Light," she actually cried a tear for a bunch of silly humans. It was probably some devious plan, she said—because, as the Doctor pointed out, the alternative was even more frightening: "The alternative is that this is for real, and it's time for us to become friends again."

And, as Bill observes this week, the question of Missy's redemption is a larger question for the Doctor himself. "She's the only person I've ever met who's even remotely like me," he says, to explain why he's so invested in Missy. "So, more than anything, you want her to be good," Bill says in response.

The Doctor wants to believe in Missy so he can believe in himself. "Am I a good man?" the Twelfth Doctor asked, way back in just his second story. And Moffat has been asking that question about the Doctor for a lot longer than that. As I've written extensively about before—here, for example, or here—Moffat has always been obsessed with the nature of the Doctor, and specifically with the paradoxes of his being both compassionate and ruthless, both a healer and a warrior, both a savior and a destroyer. Even if Moffat retconned the Doctor's greatest crimes out of continuity in "The Day of the Doctor"—erasing a darker version of the character that RTD had created—the Doctor still has a lot to feel guilty about. (Just recently, in "Extremis," we were reminded just how many deaths the Doctor has been responsible for: so many, in fact, that it caused professional executioners to run away from him.)

So the question of whether Missy is capable of redemption is part and parcel of Moffat's larger exploration about whether the Doctor is, fundamentally, a good man. It's the question, really, of what it means to be the Doctor—who, after all, must often make extremely difficult decisions for extremely high stakes, who frequently has to decide who lives and who dies, and who—as Bill learned in "Thin Ice"—cannot, always, afford to be nice. ("You were an exceptional Doctor," he told Clara, in "Flatline." "And goodness had nothing to do with it.") Does being the smartest person in the room automatically preclude the possibility of genuine goodness? (Missy seems to think so. "She's cleverer," the Doctor says to Nardole. "She's evil," Nardole disagrees. Missy, however, says it pretty much amounts to the same thing.)

So in "World Enough and Time," Missy get the chance to be the Doctor, and her playful interpretation of the role is both a sign of how far she still has to go and a dark reflection of the Doctor himself. "Well, I am that mysterious adventurer in all of time and space, known only as Doctor Who," she says. "And these are my disposables, Exposition and Comic Relief." Missy, unfortunately, doesn't get to play the Doctor for very long—he can't resist stepping in as soon as things look dangerous—but throughout the episode she still tries to play by his rules. ("Hello, ordinary person," she says to Razor. "I'm really trying not to kill anyone today. It would be tremendously helpful if your major arteries were out of reach.")

But Missy's attempt to be a hero hits a bit of snag, as she runs into her own dark reflection: her previous regeneration, the Master (John Simm). It's a nice idea for Doctor Who—there have been many multi-Doctor stories, so why has there never been a Master team-up before?—and it's a lovely way to make her truly, literally confront her own past crimes and the dark side of her own soul. Just as Moffat had to deal with the darker version of the Doctor he inherited from the RTD era (in part by having him meet his predecessors in "The Day of the Doctor"), so it's appropriate that Missy's redemptive arc has to go through Simm's genocidally unhinged Master.

"So promise me one thing, yeah? Just promise you won't get me killed."

In addition to exploring the dual nature of the Doctor, the other, deeply related central theme Moffat has been obsessed with, throughout his entire run of Doctor Who, is what I've called "The Companion Conundrum." Put simply, it's the Doctor's—and the show's—awareness that it is wildly irresponsible for him to travel with humans. "World Enough and Time" hits this theme hard right out of the gate, and indicates that Moffat still has some unresolved issues to consider on this front.

Once again, Missy provides a dark reflection of the Doctor's relationship to his companions. She calls them "disposables," and reduces them to functions ("Exposition and Comic Relief").  When they reject this interpretation, she asks, "Okay, right, so, so what does he call you? Companions? Pets? Snacks?" And, to the Doctor himself, she points out the uncomfortable truth that he has always known: that 2,000-year-old aliens can never really be friends with 20-something humans. ("Time Lords are friends with each other, dear. Everything else is cradle-snatching.")

I've written a lot about this before, and so I'll spare you a thoroughly encyclopedic accounting of how Moffat has been obsessed with this theme all along. It was the central theme of his relationship with Amy Pond, hitting its peak in episodes like "A Good Man Goes to War," "The Girl Who Waited," and "The God Complex." It became a major theme as well throughout his relationship with Clara Oswald: her becoming more and more like the Doctor became increasingly troubling in episodes like "The Caretaker," "Flatline," and "Before the Flood," and finally got her killed in "Face the Raven." And the Doctor's somewhat unhealthy, frequently dangerous influence on the people he encounters is a theme that has been echoed in other supporting and minor characters like Kazran Sardick (in "A Christmas Carol"), Lorna Bucket (in "A Good Man Goes to War"), Craig Owens (in "The Lodger" and "Closing Time"), and Ashildr (in "The Woman Who Lived"), among many others.

"You have no idea how dangerous you make people to themselves when you're around," Rory chastised the Doctor, way back in "The Vampires of Venice." And, in "The God Complex," the Doctor acknowledged how irresponsible he had been to let humans travel with him:

"I brought them here. I'd say it was their choice, but offer a child a suitcase full of sweets, and they'll take it. Offer someone all of time and space, and they'll take that too. Which is why you shouldn't. Which is why grown-ups were invented."

When I wrote about Bill's first episode, I suggested that Moffat was not quite done exploring the Companion Conundrum, and now he's seized it by the horns in "World Enough and Time," his last season finale. "Just promise you won't get me killed," we see Bill say, in flashback, when she agrees to help him "test" Missy. "I can't promise you that," the Doctor says. "I mean, look, you're human. And humans are so mortal. I mean, you pop like balloons." She jokingly asks him to at least try to keep her alive, and he says he will, "within reason."

In that flashback, we see Bill say how much Missy scares her—but Bill is brave, and she has learned to even braver while traveling with the Doctor. ("Scared is fine, scared is human," she lectured other people just last week. "But I'll tell you what it isn't. It isn't a plan.") So when Jorj (Oliver Lansley) starts waving a gun around and demanding to know who the human is, Bill barely hesitates to step forward and admit her humanity. And her reward is to have a football-sized hole blown in her chest.

Because this is Moffat—and because Doctor Who is still a show aimed largely at children—this isn't the dramatic, instantaneous death it would seem so unmistakably to be. (The classic series killed a few companions onscreen: most famously Adric in the 1982 Fifth Doctor Story "Earthshock," but also short-lived First Doctor companions Katarina and Sara Kingdom in 1965's "The Dalek Master Plan." The new series has killed one-shot companions like Astrid Peth in "Voyage of the Damned," and Adelaide Brooke in "The Waters of Mars," but any regular companions who died—Jack, Amy, Rory, River, Clara—always came back to life in one form or another.)

To me, the sudden, stupid death of a companion would be the logical and thematically satisfying culmination of all of Moffat's fascination with the "Companion Conundrum." (As much as I love Bill—and she's my favorite companion since Donna—I had about half-a-second of thrill at thinking Doctor Who might really kill her like this.) But Moffat gets to have his cake and eat it too: Bill is not dead, but what happens to her—as with what happened to Donna—may be worse: she loses her heart (symbolically, as well as literally), and by the end of this episode she has been fully converted into a Cyberman.

It's a hell of a Doctor Who cliffhanger, but it's also a familiar thematic thread from Moffat's exploration of the Companion Conundrum. We saw Rory become an Auton in "The Pandorica Opens." We saw Amy become a hardened, near-heartless warrior (with only a robot for company) in "The Girl Who Waited." We saw Amy and Rory's child Melody (later River Song) kidnapped and turned into a weapon in Season Six. We saw Craig nearly get converted into a Cyberman in "Closing Time." We saw Clara—one of her many versions, anyway—become a Dalek in "Asylum of the Daleks." We saw the soul of the Brigadier—and of everyone else who ever lived on Earth—converted into Cyberman bodies in "Dark Water"/"Death in Heaven."

These—and many other examples—can be seen as simple sci-fi tropes, obviously. But there is also a consistent theme running throughout the Moffat era: hanging around the Doctor, ordinary people run a serious risk of losing their humanity.

"It's a matter of time. Pay attention."

When I began writing this post, I started by saying "I'm going to keep my review short this week." I have since, obviously, deleted that sentence, because I realized I had much more to say about "World Enough and Time" than I'd expected. (And I haven't even discussed the episode itself that much.) I kind of love that about Doctor Who, and it's one of the reasons I write about it in the first place: stories that seem simple, once I dig into them, have a lot more going on than I'd realized.

Even the basic premise of this episode—a 400-mile-long spaceship where time is moving faster at one end than the other—is classic Moffat, both creatively and thematically. Creatively, it's a new spin on Moffat's beloved "wibbly-wobbly, timey-wimey" stuff. No showrunner or head writer in the entirety of Doctor Who history has been so enamored of the possibilities of playing with time. (As I've said before, time-travel has mostly been a means of getting to the story in Doctor Who, and only seldom a major factor in the story itself.) Moffat has always been particularly adept at using time-travel as a plot device—in stories like "The Girl in the Fireplace," "Blink," "A Christmas Carol," and many others—and he has even been good at finding ways to play with time in stories that don't explicitly rely on time loops (like Donna's experience in "Forest of the Dead," Amy's in "The Girl Who Waited," and the Doctor's in "Heaven Sent.") Here, in "World Enough and Time," he does it one more time, finding a fresh approach to time shenanigans in his final regular-season story.

But it has a thematic purpose too. It's no coincidence that I've referenced Tom McCrae's "The Girl Who Waited" so many times in this post. (And it's not just because it is one of my favorite Moffat-era stories, and certainly my favorite of those Moffat didn't write himself.) For "World Enough and Time" is something of a spiritual sister to that Season Six story. In both stories, the Doctor's trusted (and trusting) companion gets trapped in a time stream that moves at a different speed than the one the Doctor himself is in: Amy and Bill each becomes "the girl who waited," and each is ultimately disappointed and disillusioned by their faith in the Doctor. ("I waited for you" is the last thing Cyber-Bill says in this episode, a tear running down her face behind her soulless Mondasian shell.) They trusted him, and that trust was not warranted, and they each lost their humanity in the process. (Amy figuratively, Bill literally).

So it's both an example of, and an elaborate metaphor for, the Companion Conundrum. These are specific, highly problematic situations, but they are also symbols of the larger, uncomfortable truth of Doctor Who: the Doctor and his companions are going through life at different speeds. In "World Enough and Time," as in "The Girl Who Waited," the human companion loses years—and her humanity—to what is just a few minutes of time from the Doctor's perspective. That's also the larger metaphoric reality of the Doctor/Companion relationship: he's basically immortal, but his traveling companions are mortal and cursed with tragically short lifespans. It's no coincidence that, in both cases, the Doctor is in the slower timeline, while the companions' lives flash in the blink of an eye: what is a long relationship from their perspective is just a few quick moments of the Doctor's life. ("You can spend the rest of your life with me, but I can't spend the rest of mine with you," the Doctor told Rose in "School Reunion.") The Doctor describes the part of the ship he's standing in as being soaked in "Superman gravity." He's a Superman, and compared to him humans are mere mortals, as tiny, fragile, and fleeting as mayflies.

That's the conundrum, because—logically—it is wholly irresponsible for the Doctor to travel with humans. Look at the history of companions in the modern era: only Martha, arguably, came out unscathed (and even she had to have her heart broken and go through a year of purgatory in "The Last of the Time Lords"). Otherwise, Rose got trapped in another dimension, Donna got her mind erased, Amy and Rory lost their child and ended up trapped in the past, and Clara "died." Now, Bill, too, may have paid the ultimate price for her brief dalliance with the Doctor. These are not entirely happy fates.

Don't get me wrong: the Doctor's influence is good, too, obviously, and I have no doubt that every one of those people would say that the experience was worth it. (Even knowing all the dangers, none of them—none of us—would pass up the chance to travel in the TARDIS.) But it's still a problem. It is, as Missy observes, "cradle-snatching." It is, as the Doctor himself knows deep down, like "offering a child a suitcase full of sweets." It's reckless, it's dangerous, and it's really kind of selfish on his part.

But it's also an unresolvable problem, in a way that dovetails (in this episode, and elsewhere) with Moffat's other obsession: the "goodness" of the Doctor. The Doctor needs companions, in order to not lose what we can call—for lack of a Gallifreyan word—his humanity. And the Doctor knows this too, as he explained to Ashildr—another woman bitter from her time with the Doctor—in "The Woman Who Lived":

"People like us, we go on too long. We forget what matters. The last thing we need is each other. We need the mayflies. See, the mayflies, they know more than we do. They know how beautiful and precious life is because it's fleeting."

This, perhaps, is the real difference between the Doctor and Missy: the Master never really had any companions, never had anything but contempt for humans, never had anyone to care about. (In "Utopia," Professor Yana had a close companion in the kindly Chantho, but he had to kill her the moment he became the Master once more: he has no use—and perhaps even no tolerance—for emotional connections.) Missy begins her tenure as "Doctor Who" in "World Enough and Time" by expressing her disdain for her companions—she doesn't see their point—and this, perhaps, is the "music" Missy can't quite hear, as the Doctor said last week. They are what prevents Missy from being the Doctor, and they are perhaps all that prevents the Doctor from being Missy.

As I said when I began, I dislike discussing the first part of a two-part story. As we were reminded as recently as episodes six, seven, and eight of this season, Moffat has always been slightly better at planting thematic seeds than he is at harvesting them, so it remains to be seen whether his final story (barring the Christmas special) will find any kind of meaningful resolution for all of this dark subtext he has layered into his six seasons. But I'm optimistic, and the fact that we can even have the discussion—about a "silly children's show"—demonstrates that there is has been a remarkable thematic consistency, and a fairly sophisticated vision, in Moffat's era of Doctor Who. 

Additional Thoughts and Favorite Bits

• I have to gripe a little bit about marketing. I understand the practical realities of the age we live in, but how much infinitely greater would this episode have been if we had not known the Mondasian Cybermen were returning, or if we had not known that John Simm was coming back? On its own, the episode actually does a remarkable job of keeping a lid on both secrets. (Simm's disguise was good enough that I didn't recognize him until fairly late in the proceedings, and the Patients only gradually began to resemble old-school Cybermen.) In a marketing vacuum—like the one that existed around the classic series—I think both these reveals would have come as incredible, mind-blowing surprises. (And I have to single out BBC America for particular blame: the network has this annoying habit of showing teaser scenes from later in the episode during commercial breaks. In this case, they showed the "Mondasian Cybermen" revelation 20 minutes early, ensuring the surprise was spoiled for anyone lucky enough to have avoided the trailers and other warnings.)
• I have said before, and will say again: I think an excellent way to end this season would be for Missy—her redemption earned—to sacrifice herself to save the Doctor and his companions. And then the Twelfth Doctor—out of affection and homage—could regenerate, when his time comes, into Michelle Gomez, who would make a fantastic Thirteenth Doctor.  (Hey, it could happen. It probably won't happen, but it could, and it would explain why we still haven't heard an announcement about who's taking over the role. This episode even went out of its way to prepare us for that, and also to remind us that Time Lords are beyond silly concerns about gender.)
• I didn't discuss very many specifics of the episode, but I liked it very much. The concept was clever, the Cyber-Patients were creepy, and the bit with the volume-control knob was way creepy. There are minor plot-points I don't completely understand—why wouldn't the hospital just do a full conversion on Bill the moment she arrives with a hole in her chest?—but the episode was good enough that I'm not inclined to pick nits.
• Moffat, at the end of his run, is just trolling fans with that "His real name is Doctor Who" thing, right?
• I ignored my lit-major temptation to spend this entire review parsing the title, which is from Andrew Marvell's poem "To His Coy Mistress." Look it up: it will be on the final.
• See you next week for part-two, and the season finale, "The Doctor Falls."

NEXT: Episode 10×12 – "The Doctor Falls"
PREVIOUS: Episode 10×10 – "The Eaters of Light"
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