I was expecting a 'Companion has to fight a brainwashed Doctor' story which is something I don't think Who has ever done - certainly not in the new series. Instead pretty much as soon as Bill finds the Doctor it's 'Oh the Doctor was only faking being brainwashed, now let's go beat the bad guys'. Basically they promised one type of story & then gave us a completely different one. And while that *can* work it does require that the story they give us is more interesting than the story we thought we were going to get, but they were promising a interesting new take on the Doctor / Companion dynamic & then replaced it with a fairly generic story. Regardless oh good or otherwise the episode actually turns out to be that's going to hurt my opinion of it.
But just so you don't think I'm just badmouthing the episode because it wasn't what I was expecting, there were actual issues with it beyond that. The way they beat the Monks was terrible. After all the build up of 'we have to replace the Monks lies with the truth', turns out they can't do that and Bill has to use her meories of her dead mother instead. Which she *made up*. So they were *lies*. Meaning instead of an ending where truth overcomes falsehood, we get lies beating more lies, which is a fucking terrible ending thematically.
Plus the whole thing with the Doctor spending 6 months pretending to be brainwashed so he could...what? Check that Bill wasn't brainwashed? When even if she was beating the Monks would have undone the brainwashing anyway? And during those 6 months people who wern't fully brainwashed were being dragged away from their families, and if not killed at least being imprisoned?
And the Doctor is okay with this? When as far as he knew he could stop the Monks at any time?
