1) “Nova” season-opener, 8-10 p.m., PBS. Here is PBS at its best – taking an impenetrable subject and making it easy to understand – and even compelling, almost in a science-fiction way. The subject, gene-editing, is explained by animation and more. We meet Jennifer Douda, the Berkeley biochemist who linkeed with Emmanuelle Charpentier (they’re shown here, right to left) to find ways genes can be altered … and David Sanchez, 17, stricken by sickle-cell disorder. Could this be prevented? What are the ethical traps? These are compelling questions, beautifully posed.
2) “48 Hours Suspicion” debut, 10 p.m., CBS. The “Tiger King” story has intrigued people via podcasts and Netflix; now CBS News opens this temporary series with a new twist: In his feud with animal-rights activist Carole Baskin (who will be played by Kate McKinnon in a mini-series), tiger-owner Joe Exotic accused her of killing her ex-husband, Don Lewis. Now CBS interviews a woman who says her ex-husband, a handyman for Baskin and Lewis, was involved with Lewis’ disappearance.
3) “The 100,” 8 p.m., CW. A solar eclipse confounds Clarke’s scheme. Then “Coroner” (9 p.m.) takes us down to Earth, where a case has personal repercussions for Detective McAvoy.
4) “Brother vs. Brother” season-opener, 9 p.m., HGTV. The Scott twins have always had a Hollywood touch. Drew used to be an actor, getting small roles in shorts and in Vancouver-based TV shows; Jonathan was a magician until, he says, someone stole all his equipment. So this is logical: In a Hollywood-type neighborhood in Los Angeles, each brother must renovating and flip a home. Jonathan even chooses a house next to the home of Drew and his wife, Linda Phan.
5) “The Conners,” 9 and 10:30 p.m., ABC. Here are excellent episodes from opposite ends of the season. First, one of the later ones; Darlene is in jail, leaving Ben with heavy parenting duties. Then an early one; Darlene is confronted by her daughter, while navigating a tricky, two-lover lifestyle.