1) “In the Dark” season-finale, 9 p.m., CW. Last week’s episode ended with a double surprise: The good news – a sudden, passionate romance between Murphy (the blind woman obsessed with solving her friend’s murder) and Dean (the cop working the case). The bad — a cop, maybe Dean, is linked to the killing. That sets up a fierce finale, with great work from Perry Mattfeld as Murphy (shown here with Brooke Markham, left, who plays her only friend) and Rich Sommer as Dean. “Dark” ends its season and wraps its main story with some powerful jolts.
2) “Life in Pieces” series finale, 9 and 9:30 p.m., CBS. Wildly inconsistent – hilarious one moment, just silly the next – this has had an interesting, four-season run. Now it wraps its season – and (not by plan) its existence – tonight. First, Matt helps his grandfather (Paul Dooley, 91) plan a family trip to the Bahamas. Then the siblings facing life decisions: Matt has a job offer in Germany …. Greg is looking for a new house …. And Heather is thinking about having another baby.
3) Democratic debate, 9-11 p.m., NBC. On Wednesday, 10 candidates (chosen semi-randomly) had their turns. Now 10 more appear, including frontrunners Joe Biden and Bernie Sanders. Others are Kamala Harris, Kirsten Gillibrand, Pete Buttigieg, John Hickenlooper, Eric Swalwell, Andrew Yang, Michael Bennet and Marianne Williamson.
4) “iZombie,” 8 p.m., CW. Twenty years ago, a beauty-pageant contestant slipped into a coma; now that she’s died, another contestant can be charged with murder. Alas, this requires Liv to munch the victim’s brain … and develop a pageant personality.
5) “Young Sheldon,” 8 and 8:31 p.m., CBS. It’s a slow Thursday for comedy – no “Big Bang” or “Mom,” no NBC comedies. That leaves “Life in Pieces” and these two fairly good reruns. In one, Sheldon practices for college by moving in with John Sturgis; in the other, he runs for class president.