TELEVISION

■ The title tells the tale: “Expedition Deep Ocean” follows adventurer Victor Vescovo and a team of scientists in a bid to descend to the bottom of the world’s oceans. Vescovo takes the helm of what’s described as a “purpose-built” submarine to reach the lowest depths of the Atlantic, Pacific, Indian, Arctic and Southern oceans. The risks include seismic fault zones, icebergs and tropical storms, with the chance to chart new realms among the rewards. The mission unfolds over five hours debuting today on the discovery+ streaming service.

■ Rebel Wilson hosts ABC’s “Pooch Perfect,” a competition series in which dog groomers display their skills for a shot at a $100,000 prize. Lisa Vanderpump, groomer Jorge Bendersky and veterinarian Callie Harris judge the eight-episode contest, which debuted Tuesday and is based on a show in Wilson’s native Australia. The actor boasts credentials for the job: She comes from a long line of handlers and groomers — her mom judges dog shows internationally — and as a child she traveled to shows with her family.

■ Legendary gospel singer Mahalia Jackson gets overdue bio-pic attention in a Lifetime film debuting Saturday. “Robin Roberts Presents: Mahalia,” produced by the “Good Morning America” anchor, stars Danielle Brooks (“Orange Is the New Black”) as the recording artist who gained international acclaim. Also an ardent supporter of the 20th-century U.S. civil rights movement, Jackson shared her voice at rally after rally, including the 1963 March on Washington. The movie’s cast includes Joaquina Kalukango, Jason Dirden, Olivia Washington and Rob Demery.