Jessica Chastain treads the boards on Saturday Night Live (Screenshot: YouTube)

Here’s what’s happening in the world of television for Friday, January 19 and Saturday January 20. All times are Eastern. 

Top pick

Saturday Night Live (Saturday, NBC, 11 p.m.): Molly’s Game star Jessica Chastain hosts Saturday Night Live for the first time this weekend, which is a potentially risky move. She’s obviously no stranger to pressure, having led several high-stakes dramas, including Zero Dark Thirty and The Huntsman: Winter’s War, but she’s not exactly known for her improv skills. Chastain might also end up distracted by her simmering feud with SNL cast member Kyle Mooney, which this promo does little to clarify. Dennis Perkins has a theory that it all started with Mooney calling Chastain “Bryce Dallas Howard,” but we’ll find out Saturday night.

Regular coverage

Marvel’s Agents Of S.H.I.E.L.D. (Friday, ABC, 9:01 p.m.)

Wild card

Grace And Frankie, season-four premiere (Netflix, Friday, 3:01 a.m.): The next chapter in this coming-of-twilight-age story starring Jane Fonda and Lily Tomlin is here. In season four, Grace and Frankie try to empower younger women as their kids try to get them to accept their limitations, while Robert and Sol (Martin Sheen and Sam Waterston, respectively) test the boundaries of their relationship. And Lisa Kudrow joins the mix as a—you guessed it—kooky aesthetician.