‘Only Murders in the Building’ doesn’t miss a beat in getting back on the case

Understandably determined not to mess with success, “Only Murders in the Building” returns with a second season that self-consciously plays to its strengths, while layering the new mystery laid out by its cliffhanger ending on top of the old one. It’s every bit as breezy and fun, with lots of winking references to “Season 2” (the podcast, naturally, but you get the idea).