This is the worst building up of a climax that I've seen in the entire NuWho series. I can't say I care about watching the denouement next week. I will, but only because I enjoy Mr. Capaldi.
The pre-titles sequence is presented in a way that left me completely indifferent. This isn't great writing, but maybe it would have worked if Mr Pink was portrayed by someone capable of conveying an emotion. His performance all along the episode is pathetic, and that's terrible because this character is so central to today's plot.
Ensues a lot of talking, with repeated promises of disturbing explanations that end up being absolutely not disturbing, and a series of revelations that completely fail to surprise and completely succeed in demonstrating that Mr Moffat is all happy with cheap tricks. Plus we already knew we would have boring Cybermen agaaaaaain, thanks to last week's teaser; shame on that.
Let's also mention a number of plot holes, the fact that Missy, although an interesting character and actress, is more silly than creepy, and above all, once again, the fact that whatever the Doctor is doing alone on another world when he is called by Clara seems much more entertaining than what we are given to see.
As people often say on this website... Meh.