1) “Roots” (shown here), 3-10 p.m., Sundance. As Black History Month begins, here’s one of TV’s great projects, portraying the slavery experience. It set ratings records in 1977, then won nine Emmys and a Peabody. Tonight has the first half, with the rest airing from 3-10 p.m. Tuesday. This part also reruns from 8 a.m. to 3 p.m. Tuesday, so you can catch the epic in one 14-hour sweep.
2) “9-1-1” and “9-1-1: Lone Star,” 8 and 9 p.m., Fox. Austin and Los Angeles are 1,377 miles apart, but this night manages to merge the two shows. In the first hour, we see Hen (Aisha Hinds) feud with a medical-school lab partner … then join Buck and Diaz, on a mission to help fight a wildfire. That’s where the second hour finds them, helping the Texans. It’s a strong hour that ranges from fiery action to some quietly moving, edge-of-death moments between Owen (Rob Lowe) and Hen.
3) “Plan 9 From Outer Space” (1959), 8 p.m, ET, Turner Classic Movies. Back in 1980, a book (“Golden Turkey Awards”) declared this the worst movie ever. It has enough unintended badness to make it great fun. There are Bela Lugosi scenes (barely related to the story) that were shot for a different movie; after Lugosi’s death, the same character was played by a chiropractor who’s a foot taller. The spacecraft (clearly a toy) is a disc, but is vertical on the ground. Dialog rambles, furniture is cheap, logic fades.
4) “Bob (Hearts) Abishola,” 8:30 p.m., CBS. This rerun juggles two stories, one lame (Bob’s sister is falling for one of their employees) and one first-rate: Bob’s ex-wife (Nicole Sullivan) is trying to get back into his life; Abishola is not happy about this.
5) Cable dramas. At 9 p.m. (rerunning at 10:02), TNT’s “Snowpiercer” sees the two trains (now connected) make an exchange. At 10, AMC’s “The Salisbury Poisonings” has the second of four excellent episodes. A spy (Russian-born, but a double agent for England) and his daughter were poisoned. Now we focus on Tracy, new to her job as health officer … Nick, a cop who’s suddenly stricken … and Dawn, who will be key in the final hour.