30 Rock
NBC, 8:30 p.m. ET
NEW TIME: Just as Liz (Tina Fey) seems to be getting an actual, stable love life on track, her ex-boyfriend Dennis returns unexpectedly – and, of course, inconveniently. And he’s played, hilariously as always, by Dean Winters, so it’s no wonder he’s wreaking havoc. He’s been having a blast in Allstate commercials lately, playing the wickedly destructive Mayhem. (“Recalculating!”)