Before The Flood - Review

My review of the first part of this story posed a few questions. Well, here's another. Were those questions answered in tonight's episode?
Partly, I would say. First of all, the Russian town in Northern Scotland wasn't some sort of temporal anomaly, but was explained as being a British Army / NATO training ground. There wasn't anything particularly significant about Cass not wanting Lunn to enter the spaceship. It really was just to allow one of the characters to move around the base free from attack by the ghosts, as he hasn't had the message imprinted in his mind.
There wasn't an adequate explanation as to why only ghosts could broadcast the Fisher King's rescue / come-and-invade-here signal. Nor did we find out why they were eyeless with hollow heads - obviously purely a scary design concept.
Am quite pleased with myself for guessing the way that the Doctor would get out of his predicament - that it would be he who was inside the suspension casket.
I think it was obvious that there would be some time-bending aspect to the story's resolution. The Doctor basically tampered with his own time-line - so that he could both survive and become one of the ghosts.
Which brings us to the episode's opening. This was quite unlike any pre-credit sequence we have ever seen. The Doctor speaks directly to the camera (so to us then), and tells the story of how a time-traveler going back to meet Beethoven, and finding he doesn't exist, goes on to then create the Beethoven that they traveled back in time to meet. I took the Doctor's advice and Googled the Bootstrap Paradox. It is a causal loop. Basically it allows something to exist that was never created. It is implied that the Doctor is referring to himself in this tale. Maybe.
This story to camera then has the Doctor play the opening of Beethoven's Fifth on his electric guitar - which leads into a guitar-laden version of the theme music. Far superior to the rather tinny version we usually have to put up with.

It was nice to see Paul Kaye actually get to do something this week. His wish to be dominated -personally - was rather funny. Last week two other very good actors were underused, but neither of them got to do much more this time - though Colin McFarlane's ghostly stalking of Cass, armed with an axe, was nerve-wracking.
Bennett had a few things to say to the Doctor about his moral stance. Did he allow O'Donnell to die just to prove a theory? Would he sacrifice others, so long as Clara survives?

The Fisher King was a wonderful bit of design. As I said last week, I would have preferred to have had it revealed without prior publication of photos or trailer clips (which included a scene from its demise). Note how the "Next Time" teaser deliberately did not show the dragon - the dragon which one of the trailers has already shown.
There has been talk of Toby Whithouse as a potential replacement for Steven Moffat when he finally goes. His previous Doctor Who stories haven't really shown that potential, as far as I'm concerned, but some more writing like these last two episodes and I might be willing to see him have a crack at it.
Looking to the future, O'Donnell mentioned a few of the Doctor's adventures which she had read about in the files. One of these the Doctor hadn't any knowledge of - so something from his own personal future. Another "Mighty Zodin", or something more significant...?