1) “All That” opener, 8:30 p.m., Nickelodeon; reruns at midnight. Long before he became an eternal “Saturday Night Live” star, Kenan Thompson did this kid-themed sketch show (shown here). He was 15 when he started there; at 41, he’s back to help produce this reboot. Kel Mitchell (who co-starred with Thompson in the original, then in a series and a movie) is also producing. Two of the other originals (Josh Server and Lori Beth Denberg) show up tonight, with the Jonas Brothers as guests.
2) “Saturday Night Live,” 11:29 p.m., NBC. And yes, you can still see Thompson here, as always. He’s done 16 seasons so far, a record for the show. This rerun is hosted by Sandra Oh, with Tame Impala as the music guest.
3) “Murdoch Mysteries” season-finale, 7 and 8 p.m. ET, and “Frankie Drake Mysteries” debut, 9 p.m. ET, Ovation. It’s a night for gentle tales set in long-ago Toronto. Early in the 20th-century, an opium bust goes bad; also, Murdoch suspects a constable is being framed. Then we meet a 1920s private-eye, a redhead (Lauren Lee Smith) with a colorful past. The mystery is so-so, but there’s a zesty, jazz-age feel … and a visit from young Ernest Hemingway, who was a Toronto Star reporter in 1920.
4) “NCIS: New Orleans,” 9 p.m., CBS. This reruns the season-opener. With Pride hovering near death in the Intensive Care Unit, his friend Gibbs (Mark Harmon) arrives to help search for the woman who tried to kill him..
5) “The Son,” 9 p.m., AMC. The flashforwards have told us that Jeannie will eventually become matriarch of this Texas empire. For now, however, she’s a troubled teen who’s missing; her grandfather Eli searches. And in powerful flashbacks, we see a devastating time for Eli, when he was living with an Indian tribe that was desperate for food and a home.