Saturday Night Live. The 38th season kicks off with Ryan Gosling as host, Jay-Z as musical guest, and three new cast members: Heidi Gardner, Luke Null, and Chris Redd. 11:29 p.m. Saturday, NBC.

Poldark on Masterpiece. Aiden Turner and Eleanor Tomlinson are back as Ross and Demelza, the fictional Cornish couple most likely to break my heart if their much-tested marriage doesn't make it. 9 p.m. Sunday, WHYY12.

Curb Your Enthusiasm. Will & Grace isn't the only show whose ninth season has been a long time coming. Larry David returns — at last — to continue his one-man charm offensive (emphasis on offensive) against the world at large. 10 p.m. Sunday, HBO.

Ten Days in the Valley. Kyra Sedgwick (The Closer) returns to TV in a very different crime drama, playing a television producer whose young daughter's disappearance exposes all kinds of secrets. After her case-of-the-week TNT drama, Sedgwick says, "I was interested in doing a show where I'm not solving a mystery. I am a mystery." 10 p.m. Sunday, ABC.

9JKL. Inspired by star Mark Feuerstein's experiences living adjacent to his parents and other family in a Manhattan apartment building, this half-hour boasts strong supporting players — including Linda Lavin, Elliott Gould, Liza Lapira, and David Walton — who, along with Feuerstein, are the reasons I'm inclined to hang in past the so-so pilot. 8:30 p.m. Monday, CBS.

The Gifted. Marvel may be everywhere, but not everything it has is marvelous (the cartoonishly bad pilot for Marvel's Inhumans on ABC, for instance). This one, set in the X-Men universe, is a solidly suspenseful family drama starring Stephen Moyer (True Blood) and Amy Acker (Person of Interest, Dollhouse) as parents forced to take their family on the run after their children (Natalie Alyn Lind and Percy Hynes White) develop mutant powers. 9 p.m. Monday, Fox.

The Vietnam War. If you missed any, or all,  of Ken Burns and Lynn Novick's 18-hour series, here's a chance to catch up, as the entire series replays in weekly installments. 9 p.m. Tuesday, WHYY12.

The Mayor. What if someone ran for public office to boost his celebrity and then unexpectedly won? Brandon Micheal Hall stars as a young rapper who does just that, and then, with the help of his mother (Yvette Nicole Brown, Community), and his opponent's manager (Glee's Lea Michele) is pushed into trying to become the leader his city deserves. 9:30 p.m. Tuesday, ABC.

Kevin (Probably) Saves the World.  Jason Ritter (Parenthood) stars as Kevin, a man who's lived a selfish life that's about to be turned upside down by the arrival of a  messenger from God named Yvette (Kimberly Hébert Gregory). Terrible title, but it's from the clever creators of Reaper — whose major characters included the Devil — so worth a look. 10 p.m. Tuesday, ABC.