This week\u2019s \u201cDoctor Who\u201d culminates a plot not just from last week, but from the 50th anniversary episode, \u201cDay of the Doctor.\u201d Still, the most important thing in it may be Peter Capaldi\u2019s one-man show, which doubles as a mission statement for The Doctor. And while Clara isn\u2019t in it much, Jenna Coleman does a great turn as her Zygon duplicate. Plus, more Osgood!