EndeavoUr 9 p.m., Channel 2
“Downton Abbey” creator Julian Fellowes has talked about a prequel series but made no promises. In the meantime, PBS people, here’s a prequel series from “Masterpiece Mystery.” It goes back to when Inspector Morse was Constable Morse and he looked more like actor Shaun Evans than John Thaw.
Carson on TCM 8 p.m., TCM
Maybe the young’uns don’t know why the calm Johnny Carson was considered the master of late night. And maybe the olds have forgotten. So, every Monday this month, TCM is cherry-picking an hour of interviews from the West Coast years of “The Tonight Show Starring Johnny Carson.” You can see his perfect timing and his spontaneity and how he made guests feel comfortable. This week he talks to Doris Day in 1976, Charlton Heston in 1976, Chevy Chase in 1986, Steve Martin in 1979, and Tony Curtis in 1973. The clips are set up by Carson fan and late-night host Conan O’Brien.
8 and 9 p.m., Animal Planet
You know how sometimes you just want to space out, or check out, or geek out? Well here’s an opportunity to pretty out, as Animal Planet takes us on a tour of the flora and fauna of some wetlands with cool names. In the first hour, it’s the Okefenokee Swamp on the border of Georgia and Florida, and in the second hour it’s the Atchafalaya Swamp in Louisiana.
Camp 10 p.m., NBC
NBC is premiering a show that has “summer” and “family show” written all over it. Rachel Griffiths plays the newly divorced owner and director of a struggling camp. While she deals with romantic feelings for a competing camp owner, her counselor son hopes to lose his virginity by the end of the season.
Summer Camp 8 p.m., USA
A TV law of motion: To every scripted action (“Camp”), there is an equal and opposite reality reaction. This new show has adults going to camp in California and playing old-fashioned summer camp games (Color War!) for $250,000. Don’t expect freshness; in advance press material, the show is typing the players with labels such as “The Geek,” “The Model,” “The Pageant Queen,” and “The Cowboy.”
Open Studio With Jared Bowen 8:30 p.m., Channel 2
This well-done weekly magazine series features the best local and national PBS arts stories, as well as interviews conducted by host Jared Bowen. In this episode, Bowen talks to Museum of Fine Arts director Malcolm Rogers as well as to Ted Cutler, founder of the new, free, massive Boston musical festival Outside the Box.
The Nightmare Nanny
8 p.m., Lifetime
Look, it’s a summer Saturday, and you’re probably better off watching “The Women” on TCM at 8 or just whittling away at your DVR queue. But if you’re feeling cheesy and easy, here’s a Lifetime movie that goes for the parental jugular. Yup, a stay-at-home mother returns to work and the nanny absconds with the child.