HBO Max Scores Exclusive ‘Doctor Who’ Streaming RightsJo Tro Do Plo Plo No: ‘Doctor Who’ Welcomes Back Familiar Monster Stay on target This article contains spoilers for “The Doctor Falls,” episode 12 of Doctor Who season 10.Doctor Who is a series of hellos and goodbyes. And it’s (almost) time for goodbye again.This year’s two-part climax—penned by exiting showrunner Steven Moffat and directed by three-time finale helmer Rachel Talalay—indulged fans in some incredible highs and devastating lows.Amidst the (not-so-surprising) return of John Simm’s Master, the transformation of Bill into Cyberman, and the general destruction of a 400-mile-long colony ship, the Doctor still manages to save the day.And all it took was a hilariously phony hunt-and-peck on a control-room keyboard, changing the robots’ algorithm to hunt two hearts as well as one.“I expanded the definition of humanity,” the Time Lord explains to childhood frenemies the Master and Missy, who deflects the oncoming storm with their respective laser screwdriver and sonic umbrella.Missy (Michelle Gomez) and the Master (John Simm) team up for destruction (via BBC)Missy, still grappling with her commitment to become good, and the Master hijack Nardole’s stolen shuttlecraft, hoping to leave an unconscious Doctor behind.But even “doomed to spend an eternal afterlife as a bio-mechanical psycho-zombie,” as Missy so eloquently put it, Bill comes to the rescue.Stuck on a sharecrop on Level 507 (a hidden Easter egg tribute to former showrunner Russell T. Davies, who tended toward “57” as a fake number, according to Moffat), Team TARDIS slowly get back on their feet: Nardole leads the farmers-cum-soldiers in war, the Doctor tends to his wounds, and Bill discovers the truth about herself.Interestingly, for the first time on Doctor Who, the audience gets to glimpse the ostensible “woman behind the mask.”It’s easy to forget that Cybermen, wholly organic humanoids that originated on Earth’s twin planet Mondas, are real people whose bodies were replaced with cybernetic parts and whose brains have been stripped of all emotions.The Doctor and the Master fight over Cyber-Bill (via BBC)But Bill, still learning the ways of the otherworldly, doesn’t know she’s been converted, doesn’t understand why the townspeople are so frightened of her—a chip server from London.Throughout this season, newcomer Pearl Mackie has repeatedly proven herself, playing Bill with so much heart, excitement, and charm that you feel the character’s every emotion—and then some when she finally gets her happy ending.Unlike Moffat and stars Peter Capaldi and Michelle Gomez, Mackie and the BBC have remained mum about the 30-year-old’s departure from the show.“She doesn’t die,” Moffat promised in an interview with The Fan Show. “She nearly dies. [But] she becomes something else,” leaving the door open to Chris Chibnall (or any future producer) to bring Bill Potts back into the Whoniverse.Bill (Pearl Mackie) has been on some wicked adventures (via BBC)Meanwhile, on the other side of the forest, the genius twins have given away their position, essentially inviting hoards of weapons-grade Cybermen to convert hundreds of harmless humans into detached droids.The Doctor, in full action-hero mode, traipses through the woods, reminiscing about past victories—”Telos! Voga! Canary Wharf! Planet 14! Every single time, you lose—even on the moon”—while zapping cyborgs in fiery flashes of glory.In an emotional ending to an otherwise erratic season, our titular warrior takes a seemingly fatal blow, just before returning the favor to the Cybermen; and, fittingly, Missy and the Master stab/shoot themselves in the back.But with a star flaming explosion in his eye, the Doctor is met once more by Bill, who has somehow survived the apocalyptic attack to return him to the TARDIS, where he can rest in peace.Or not.Peter Capaldi is the Twelfth Doctor (via BBC)The final hour-long episode injects doses of nostalgia with lines like Missy telling the Master “I loved being you” (the same thing the Tenth Doctor tells the Fifth when they meet in “Time Crash”). And “Without hope, without witness, without reward” (the Twelfth Doctor’s repeated words from “Extremis”).It also recalls the Fourth Doctor’s love of Jelly Babies, various ways the Time Lord has died, and places and planets identified with Cybermen.But anyone (including myself) who hoped the Monks’ alternate reality would actually pay off in the end shouldn’t hold their breath for a shocking return in this year’s Christmas special.What you can expect, however, is the First Doctor (portrayed by David Bradley), the (rumored) return of Jenna Coleman as Clara Oswald, and Peter Capaldi’s long-awaited (but heavyhearted) regeneration into a mysterious Thirteenth Doctor.(Could Moffat have hidden a clue to the next actor’s identity in his penultimate script? When Bill’s Cyberman steps forward to fight the approaching enemy, the Master sorely asks “Will the future be all girl?”, to which the Doctor replies, “We can only hope.”)Missed episode 11 of Doctor Who? 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