12th Doctor and Clara Oswin Oswald
For the most part, I really enjoyed it. It was funny, there were plenty of references for long time fans, nods to past Doctors, and Moffat even cleverly touched on a lot of questions people had expressed about Capaldi's casting. I felt that the scenes with The Doctor in the alleyway with the tramp were some of the most poignant scenes in the whole episode. His disorientation was both amusing and troubling; you really felt for him as he tried to piece together who he is.