1) “Transplant” season-finale, 8 p.m., NBC. It’s a pivotal episode for this well-made Canadian show, with huge changes, plus cliffhangers. Bash (shown here), a Syrian refugee, saved the life of Bishop (the emergency room chief), who later vouched for him despite a lack of paperwork. Then there’s the intense Mags … and the closed-off Jane … and Hunter, who retreated to a far-away job. There are also key moments from patients, including great scenes with one in her 90s.
2) “Saturday Night Live,” 11:29 p.m., NBC. In this rerun, Lizzo is both the host and music guest. She joined a small list of people who have done double-duty. The first was Ray Charles in 1977 (the third season); most recent were Nick Jonas last season and Billie Eilish and Lizzo this one.
3) “Flowers in the Attic: Origins,” 8 p.m., Lifetime. A gloomy tale unfolds over four Saturday movies. Last week’s opener (rerunning at 6 p.m.) introduced Olivia as a bright businesswoman, courted by wealthy Malcolm, who turned cold and controlling – until she gained some leverage. Now the mansion includes his father’s young widow and more crises, including secrets and a fake pregnancy.
4) “Claim to Fame” and “The Final Straw,” 9 and 10 p.m., ABC. Here are quick reruns of two new summer shows. (ABC’s third new one is “Generation Gap,” at 9 p.m. Thursdays.) These follow a rerun of the “America’s Funniest Home Videos” Easter hour. “Claim” has 12 people who are secretly kin to someone famous … something Frankie Jonas (hosting with his brother Kevin) understands. “Straw” has odd variations on Jenga-type towers.
5) World Athletic Championships, 3-5 p.m. and 9-11 p.m., NBC. It’s the first weekend of an event with 1,900 athletes, including 42 Olympic gold-medalists. NBC continues from 2-4:30 p.m. and 10-11 p.m. Sunday; then coverage returns to the USA Network and Peacock, before NBC’s finals next weekend.