1) “Snowfall” season finale, 10 p.m., FX, rerunning at 11. Some fierce collisions have been propelled by two things: A reporter (tipped by Franklin’s father) wrote about Teddy’s CIA guns-for-drugs scheme; also, Leon accidentally killed the niece of Manboy, a rival gang boss. (Franklin, Leon and Manboy are shown here.) Last week, Teddy killed the reporter after a car crash; Franklin killed Manboy and his gang. Here are the aftershocks, some quiet and some not. This would be a great series finale, but “Snowfall” will return.
2) “Nature: Sharks of Hawaii,” 8 p.m., PBS. On Thursday, TV will celebrate Earth Day with a splendid surge of nature films. While we’re waiting, we can catch this excellent one. It focuses partly on Hawaii’s thriving sharks, but also detours into other intriguing underwater views.
3) “Chicago Med,” 8 p.m., NBC. Ethical questions tug at the drug trial Will has been conducting. Also, in this rather heavy-handed hour, Dr. Charles cautiously meets an obsessive patient and Dr. Archer (Steven Weber, a newcomer to the show) faces a perilous field assignment.
4) “The Conners,” 9 p.m., ABC. Last week, Becky reluctantly agreed to go to rehab. Now her nephew Mark is stressed and exhausted, while studying for an entrance exam. Darlene (Mark’s mon) comes up with a plan to help, but it soon fizzles.
5) “Pillow Talk” (1959), 8 p.m. ET, Turner Classic Movies, or “Silver Linings Playbook” (2012), 9 p.m., Showtime. Comedies are usually ignored at Oscar time, but these two clever films are exceptions. “Pillow Talk” won for best original script and was nominated for three more, including Doris Day as best actress. “Playbook” won for actress (Jennifer Lawrence) and was nominated for seven more, including actor (Bradley Cooper), script and best picture.