The Highwaymen: Friends Till the End (9 p.m., UNC-TV) – “American Masters” profiles the country music group made up of Willie Nelson, Waylon Jennings, Johnny Cash and Kris Kristofferson through interviews and vintage performances. The special provides insight on life on the road and in the studio. A repeat of Willie Nelson’s Gershwin Prize Tribute follows at 10.
Also on tonight . . .
Geo Bee 2016 (8 p.m., National Geographic) – The 28th National Geographic Bee tests the brain power of geography buffs in Washington, D.C. Mo Rocca hosts.
Urban Predator: Lion on the Loose (9 p.m., Animal Planet) – Renowned game tracker and animal activist Rory Young travels from Africa to search for an African lion caught on a cellphone video, terrorizing the streets of Milwaukee.
Wynonna Earp (10 p.m., Syfy) – Wynonna tries to get past her encounter with the last of the Seven, and gets swept up in Henry’s vendetta.