My favourite part of this episode was the performance of the Master in disguise, whom I shall call Zathras.
The ship was a beautifully creepy setting. A setting like that deserves a full novel, not just a couple of episodes.
Re: Bill’s conversion: In a show where realistic world simulation computers are a thing, I don’t trust what I see on my screen. The Doctor has had this longstanding dilemma of “Can Missy be trusted?”, and he had access to Monk technology for several months. You see where I’m going with this. For most shows, this’d be overthinking it, but the Grand Moff likes his convoluted series arcs, revisiting things from earlier in the season.
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