*This review is cross-posted to the Krewe du Who blog*
As always, DO NOT READ unless you're caught up on Series 9 of Doctor Who! As River would say: *spoilers*
This week's episode concludes the latest two-parter for Series 9 and officially acknowledges the show's use of ontological paradoxes as of late (though they use the more colloquial term, bootstrap paradox, it's the same thing). The ontological paradox is a common theme in time travel, and while I personally think that getting caught in that trap is very easily overused, I appreciate the show taking a few moments to at least explain what they are and acknowledge that they leave the audience with more questions than answers. I also appreciate that The Doctor broke the fourth wall in order to explain the paradox to the audience. Attempting to put all of that information directly into the show's dialogue would have been awkward at best, and this approach allowed for the effortless call back at the end of the episode.
Before the Flood also included references to the Arthurian legend and the Celtic myth of the Fisher King/Bran the Blessed. Despite naming this week's big bad The Fisher King, the actual legend was only vaguely touched on and some pretty important elements were left out. Specifically, The Fisher King was not (in any discernible way) wounded and was certainly more than capable of moving about unaided. It's concievable that the suspended animation chamber and the significance of the temple/church as The Fisher King's final coordinate could be a reference to the Holy Grail, though the fact that the ghosts are incapable of speech is more closely related to Bran's Cauldron (which had the power to resurrect the dead, but those resurrected lost their ability to speak). In what may be an even further stretch, the question of who originally gave The Doctor the words to have his hologram relay to him could be a take on the healing question Percival must ask The Fisher King in order to heal him in early tellings.
Yet another theme throughout the episode is love and loss. They briefly touched on Clara's refusal to properly deal with Danny's loss in Under the Lake, but they've practically smacked us in the face with it this time. First we have Bennett's grieving over O'Donnell (and his outrage toward The Doctor for doing nothing to save her but rewriting history to save Clara). Then he practically forces Lunn to admit his feelings to Cass. There are a few references to Clara using The Doctor and the TARDIS as a means to escape her feelings. Finally, we're treated to Clara explaining to Bennett how to move on with his life without O'Donnell. She's using a mixture of escapism and pragmatism rather than properly grieving; essentially, the TARDIS is her opiate. Clearly that's going to be a theme this series, and perhaps it will play into her inevitable exit from the show.
Truly this series has been a vast improvement over series 8, and I sincerely hope we continue to get decent writing as the series progresses (but please, please get rid of the sonic shades!).