Overall a distinct and exciting episode, best since the series opener. Introducing the time jumps and a more concise contained plot makes the show sing better. 1920s Jack Harkness, an exploration of his immortality and the way he has been mistreated by people he has put trust in is a delicious thing to watch unfold. Seeing Gwen have to turn on Jack and getting some high quality time with characters I am actually invested in, in the modern day scenes, also gives some much needed dynamism to a series which has sorely lacked interest. The sexy dialogue though. Oh my dear GAWD please NO! One of the cringiest things to ever happen in Doctor Who.