Tonight’s Doctor Who is a turning point for the season. After a run of standalone adventures for the Doctor (Peter Capaldi) and Bill (Pearl Mackie), by the end of “Extremis” we’re suddenly in the middle of a big multi-part tale. It feels quite similar to the way 2011’s mid-season finale, “A Good Man Goes to War,” finally resolved the long-running mystery of River Song’s identity, only for that resolution to send the season’s plot arc off in a whole new direction. Ever since “The Pilot,” we’ve been teased with the riddle of who or what is in the secret vault that the Doctor and Nardole (Matt Lucas) have been guarding, and why the Doctor took up this duty. “Extremis” fills in the answers to those questions, but it’s clearly only the prologue to a much larger story.
Showrunner Steven Moffat’s plotting ingenuity is on full display throughout, as he structures the episode to conceal for as long as possible that audiences are actually watching two completely separate stories. What appears to be the main plot involves the Doctor being requested by the Pope to investigate the Veritas, an ancient manuscript in the Vatican’s library of forbidden texts. Its language opaque for centuries, it’s finally been translated—and all who read it almost immediately commit suicide, as is graphically illustrated by an unsettling scene involving one of the translators, who’s emailed the document to various organizations around the world.
The Doctor is still blind after last week, which precludes his usual madcap rushing around; Bill and Nardole provide all the light relief in this otherwise grim episode. Nardole’s attempts to cover for the Doctor’s condition are endearing, and Bill has a funny moment when she brings a date home only to find an unexpected Pope in her bedroom. Later, Lucas and Mackie make a great team when Bill and Nardole, for the first time, share substantial screen time together without the Doctor as they investigate a series of strange portals that link the Vatican library with other locations including the White House, the Pentagon, and the famed particle physics laboratory at CERN.
The portals are the work of an alien race looking to invade Earth, and director Daniel Nettheim takes advantage of the Doctor’s blindness to keep the appearance of the creatures from viewers for as long as possible. When they’re finally seen, with their faces looking like decaying corpses, they make quite an impact. The true shock, though, comes with the realization that all of the places linked by the portals aren’t real—it’s all a computer simulation being run by the aliens to gather information about Earth and humanity in advance of their invasion. Even the Doctor and his friends are part of it. After creating a whole string of creepy and macabre monsters and situations in his time with Doctor Who, Moffat has now come up with a purely existential threat: not just “the world is not what you think it is” (as in 2008’s “Silence in the Library”), but “you are not who you think you are.” As first Nardole and then Bill come to understand their own unreality, Lucas and Mackie effectively convey the horror of the realization as they fragment and vanish.
Meanwhile, what’s happening in the real world is quite different. The blinded Doctor is simply standing outside the doors of the vault, remembering. Moffat fills in the gap in the Doctor’s life between 2015’s “The Husbands of River Song” and this season, showing how after River’s death he found himself tracked down by a mysterious sect who’d captured Missy (Michelle Gomez) and required him—as the only other Time Lord they could find—to participate in her execution. He eventually went through with it, giving a solemn oath to keep her body in the vault, and guard it for a thousand years. But, amusingly, his oath never promised that she had to be dead during that time, so he interfered with the termination equipment, keeping her alive.
We saw in 2014’s “Death in Heaven” that the Doctor and Missy’s feelings for each other are a complex mix of enmity and friendship. The Doctor seems impelled to keep reaching out to Missy even against his better judgment; she, in turn, promises here to “turn good” and wants to be his friend. Gomez and Capaldi are again compelling in their confrontation, and even though Missy is presumably play-acting, Capaldi makes it completely understandable that the Doctor’s loneliness would lead him to keep giving her one more chance. And in case the Doctor was in danger of being left looking weak, Moffat gives him a chance to swagger again as he scares off the protesting executioners with a repeat of the “look me up” gambit that David Tennant’s Doctor used to intimidate the Vashta Nerada in 2008’s “Forest of the Dead.”
It’s only at the end of “Extremis” that the two stories finally intersect. The simulated Doctor neatly hoists the enemy on their own petard by exploiting the very faithfulness of their simulation. Being just as blinded as his real counterpart, he uses the software on the translator’s laptop to read the translation aloud to him, and then manages to send a recording of it and all the events he’s witnessed to the real Doctor—information, of course, being the one thing that can escape from a computer simulation into the outside world. It’s this message from his simulated self that the real Doctor has been experiencing outside the vault, at the same time as he has been remembering the events of long ago. The episode’s unusually contemplative final scene can hardly be called a cliffhanger, even though everything is left up in the air: The Doctor, now fully cognizant of the alien threat, realizes he may have to rely on Missy’s help if he’s to defeat them. It seems he’ll soon be finding out exactly how much her declaration of friendship is worth.
Next Week: The struggle against the aliens intensifies, in “The Pyramid at the End of the World.”
Classic Doctor Who Recommendation: Another case of alien invaders using a simulated Earth environment to prepare for their assault can be found in 1975’s “The Android Invasion,” starring Tom Baker and Elisabeth Sladen.
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