It really is. I wonder if it's going to be gearing up to some kind of reunion of characters like a lot of Eleven's arcs did.

There was someone (and now I can't for the life of me recall who) who wrote a meta on how they think everything is gearing up to some kind of trial of the Doctor, and it was very convincing (to me, anyway). I feel like the characters being grabbed by Missy are for the prosecuting argument. I wonder if the characters in the episodes where we don't meet Missy will be forming the defence.