TV TOP PICKS

6 p.m. on CNN CNN Democratic Debate

From the campus of Otterbein University in Westerville, Ohio, the dozen qualifying candidates for the 2020 Democratic presidential nomination gather for their party’s fourth sanctioned primary debate. Moderators for the three-hour broadcast are CNN anchors Anderson Cooper and Erin Burnett, along with New York Times national editor Marc Lacey. Topics have not been announced in advance, but the current U.S. House of Representatives impeachment investigation of President Donald Trump seems likely to loom large.

7 p.m. on FOX

The Resident

Conrad (Matt Czuchry) begins to doubt Devon’s (Manish Dayal) judgment after one of the latter’s patients suddenly revives after being pronounced dead, in the new episode “Belief System.” Cain and Nic (Morris Chestnut, Emily VanCamp) clash over how to deal with their latest patient, a well-known white supremacist. En route to a medical convention, The Raptor and Mina (Malcolm-Jamal Warner, Shaunette Renee Wilson) are stranded in a strange town, where they stumble across new information about Red Rock Medical.

8 p.m. on CW

Arrow

Oliver (Stephen Amell) is still trying to figure out the nature of The Monitor’s (guest star LaMonica Garrett) mission as he returns home to encounter some familiar faces in “Starling City,” the premiere of the eighth and final season of this superhero drama. Elsewhere, Mia (Kathleen McNamara) and William’s (Ben Lewis) team clash with a new foe.

8 p.m. on USA

Treadstone

Sleeper agents around the world are awakened to undertake the covert missions for which they were programmed in this sleek new spy drama from some of the producers on the Bourne movie franchise. In fact, this series is set in the world of the same secretive CIA initiative where super-spy Jason Bourne started, although while that character is mentioned, he never appears here. Jeremy Irvine, Brian J. Smith and Michelle Forbes star.

9 p.m. on PARMT

Battle of the Fittest Couples Ex-Bachelorette JoJo Fletcher and former NFL quarterback Jordan Rodgers, a real-life couple themselves, host this new reality competition series, in which 12 couples from around the United States compete in a series of grueling physical challenges for the chance to win $100,000 and the title of Fittest Couple. Hometowns represented include Los Angeles and Sacramento, Calif.; Tampa, Fort Lauderdale, Casselberry and Windermere, Fla.; Maui and Pahoa, Hawaii; Mechanicsburg, Pa.; Dalton, Ga.; Charlotte, N.C.; and Columbus, Ohio.