1) “Snowpiercer” season-finale, 9 and 9:58 p.m., TNT. As the current heat wave grips much of the country, here’s the exact opposite: The temperature outside is minus-122 Celsius, which is worse than it sounds; in Fahrenheit, we’re told, that’s minus-188, People are safe only as the train keeps moving. But inside the train, Daveed Diggs and Jennifer Connelly (shown here) battle for control. And outside, there are potent new forces. It’s a tautly crafted finale, but don’t expect an ending. Mostly, this propels us to next season.
2) “Hightown” season-finale, 8 p.m., Starz. For Jackie (Monica Raymund), this is overwhelming. “I’d never seen a dead body in my life,” she says. “Now there are bodies everywhere.” She’s a Cape Cod fisheries officer (and a recovering alcoholic), wedged into a dark investigation. That reruns at 10:02 p.m. and 1:02 a.m., on a night that also debuts “P-Valley” (set in a Mississippi pole-dancing bar) at 9 p.m., rerunning at 11:02 p.m. and midnight.
3) “Masterpiece: Grantchester,” 9 p.m., PBS. This season has been surprisingly dark and disturbing. It will perk up in next week’s season-finale, but first things hit bottom: Will, the good-hearted vicar, takes pride in his boxing program for troubled boys. Then comes a disaster, leading to shattering revelations.
4) “Masterpiece: Beecham House,” 10 p.m., PBS. A week from the season-finale, John’s world is shaky: A widowed father, he doesn’t know that his friend, Capt. Parker, is betraying him. And he’s agreed to a secret task: Sell a diamond that the prince took from the emperor’s treasury, to finance the emperor’s army. Tonight – in an eventful but stiffly executed hour – the troubles build.
5) ALSO: At 7:10 p.m., HBO has the pleasantly odd movie, “Last Christmas” (2019). At 9 (rerunning at 10:03), Paramount’s “Yellowstone” has John (Kevin Costner) confronting hostile trespassers. And at 10 ET on Fox News, Nancy Grace hosts “The Twisted World of Jeffrey Epstein.” It ranges from Epstein’s childhood to his apparent suicide in a jail cell, after being charged with sex trafficking.