What’s On: Travel the globe with ‘Planet Earth II,’ and ‘The Good Wife’ spins off with Diane at center stage

Planet Earth II (Saturday, 9/8c, BBC America): Continuing the dazzling legacy of the global nature-TV phenom of a decade ago, with new technology allowing viewers to get even closer to the wildlife and remote wilderness vistas, Sir David Attenborough returns to narrate these visually stunning vignettes of survival from some of the most exotic corners of the world. Night One focuses on island life, with an amorous pygmy three-toed sloth seeking love in the Caribbean, newly hatched iguanas in peril on the Galapagos, and in sub-Antarctica, you guessed it: penguins!

The Zoo (Saturday, 10/9c, Animal Planet): For a more accessible look at animal life, this new series spent eight months inside the world-famous Bronx Zoo, with an emphasis on animal care—including a silverback gorilla with glaucoma—and the zoo’s efforts at species conservation.

The Good Fight (Sunday, 8/7c, CBS and CBS All Access): Christine Baranski takes center stage as Diane Lockhart in this sensational spinoff of The Good Wife, slapped by misfortune and joining a new firm, where she works alongside the dynamic Lucca (Cush Jumbo) while mentoring her own disgraced goddaughter (Rose Leslie). Unfettered by network content limitations, this Fight is as sexy and saucy as it wants to be, but maintains the wit and sophistication of the original series. After the first episode, though, the show is available only to subscribers of CBS’s All Access streaming service.

The Paley Center Salutes NBC’s 90^th Anniversary (Sunday, 9/8c, NBC): Reaching back to its first radio broadcast from the Waldorf-Astoria as an RCA property to the current home of hits including This Is Us and The Voice, this clip-filled retrospective of the pioneering broadcast network promises to be an orgy of nostalgia. Depending on your age, you might thrill to scenes from Bonanza, Laugh-In, Hill Street Blues, St. Elsewhere, L.A. Law, The West Wing, The Golden Girls, The Cosby Show (even now), Friends, Seinfeld, Cheers, Frasier, Law & Order and so many more.

Inside Weekend TV: Showtime’s free preview weekend, from Friday to Monday, culminates in the second-season premiere of Billions (Sunday, 10/9c), with Damian Lewis and Paul Giamatti once again facing off as combative titans of politics and high finance. … HBO’s Crashing (Sunday, 10:30/9:30c) stars Pete Holmes as a sad-sack nebbish of a stand-up comic who leeches off the likes of Artie Lange. It’s Louie without laughs. … Roy Wood Jr., one of the brightest lights of the current The Daily Show cast, gets his own stand-up special in Comedy Central’s Father Figure (Sunday, 11/10c).