Officially, the plot is simple -- a Dalek malfunctions and develops a moral code, and the obvious solution is to re-enact the 1987 cult hit "Innerspace." “The most dangerous place in the universe," we're told, although I think the people on the outside of the Dalek would disagree. Cue lots of eerie lighting, croaks of "Exterminate!" and a chance for the Doctor to scoff at soldiers.
Really this is a chance for Peter Capaldi, somewhat wasted in his first proper appearance, to shine. Ever since the show came back in 2005, it's flirted with a darker Doctor -- Eccleston's excellent performance in "Dalek," Tennant's personal apotheosis in "The Waters of Mars," "The man who can turn an army around at the mention of his name" in "A Good Man Goes to War." Now it seems that they're actually delivering.
We're treated to the full context of that delicious scene from the early trailer, where the Doctor asks Clara if he's a good man and we see that it's because he's questioning his entire moral compass. If Daleks can be good, can the Doctor be bad? It's an interesting conclusion to an arc of reckless decisions from the Time Lord, and Capaldi conveys a mix of guilt, revulsion and cold-hearted pragmatism. He can't hide behind the boyish good looks anymore, so this is the Doctor as he's always been -- care-worn, old and jaded. His speech to Rusty the Dalek revives his own enthusiasm for the universe, which makes the kernel of hatred he still carries around all the more poignant.
Capaldi's off-hand confidence is appealing -- after the last two leads, who had an occasional tendency to overact, his restraint is enjoyable. This is a Doctor who could care less about proving himself -- he has worlds to save and coffee to deliver to Clara. He's reminiscent of Tom Baker at his best: None of the showy stuff, but just enough surreality to remind us that he may look human but he isn't.
Speaking of the Doctor and Clara, their dynamic was spot-on this episode -- his gruff restraint actually gives Jenna Coleman something to play off, and their snarky odd couple vibe gave Coleman some of her best moments yet. Despite last season's forgettable Impossible Girl plotline, Clara is the most ordinary companion the Doctor has seen in a while and it works beautifully.
Unlike Amy and Rory, Clara isn't waiting on tenterhooks for him to return, and she doesn't need to be whisked away from the mundanity of her existence like Rose. "You're one of my hobbies," Clara informs him when he absent-mindedly tries to work out if he pays her or not (fair enough, but being a teacher's salary isn't that much, she at least deserves danger pay for repeatedly nearly getting killed).
Clara's "take it or leave it" attitude works much better with the more restrained Capaldi than it did with the puppyish Matt Smith. Whereas Eleven thrived on human interaction, you get the sense that Twelve would happily carry on a conversation by himself for days and only notice when he needs someone to hand him the sonic screwdriver. I think he might actually believe that Clara lives in a cupboard when he's not with her.
Once again we're spoiled for choice with supporting characters -- Zawe Ashton (of the British comedy-drama "Fresh Meat") as the stubborn, gutsy Journey Blue reminded viewers once again why she could carry her own series and not break a sweat, and Samuel Anderson's Danny Pink is a very promising love interest for Clara. His past was laid on a bit thick, especially the comment about being a ladykiller: I'd put money on him having shot, either accidentally or on orders, the woman he loved. Or maybe a child (which would explain his move into teaching). Either way, his military past could be mawkish, but Anderson's macho but funny performance -- part tough guy and part awkward geek -- is the cherry on top of this episode's cake.