The Vikings (9 p.m., History) – In the Season 4 finale, Prince Aethelwulf finds himself subject to the Vikings’ battle master plan, while Ecbert remains behind with a plan of his own.
Also on tonight . . .
Spy in the Wild: A Nature Miniseries (8 p.m., UNC-TV) – The start of a miniseries featuring wild animals, including wild dogs, elephants and monkeys.
The 100 (9 p.m., The CW) – In the Season 4 premiere, Clarke and her friends struggle with how to proceed after learning the fate of the world.
Star (9 p.m., Fox) – Star, Simone and Alex get an invitation to perform at a charity event, and Star manages to steal the spotlight even though Jalil put Alex in the lead.
The Carbonaro Effect (10 p.m., truTV) – In the Season 3 opener, Michael proves you are what you drink.
Suits (10 p.m., USA) – Harvey tries to repair a broken relationship.