Whose Line Is It Anyway? (7 p.m., CW/Ch. 30) is the most successful comedy The CW has ever put on the air. So successful the network has already ordered another 24 episodes.
Tonight’s guests include Kyle Richards and Jonathan Mangum.
Elsewhere on TV ...
America’s Got Talent (8 p.m., NBC/Ch. 5): The auditions continue.
So You Think You Can Dance (7 p.m., Fox/Ch. 13): The remaining 14 contestants perform; two are eliminated.
Rizzoli & Isles (7 and 9 p.m. TNT): Jane’s appearance in a viral video threatens her career.
Big Brother (8 p.m., CBS/Ch. 2): The veto competition takes place.
Perception (8 and 10 p.m., TNT): Pierce and Donnie investigate the malfunction of a brain device.
Pretty Little Liars (9 p.m., ABC Family): Hanna comes up with a desperate plan.
Frontline (9 p.m., PBS/Ch. 7): A look inside the largest assisted living company in the United States.
Twisted (10 p.m., ABC Family): Danny is tormented by masked pranksters.
Who Do You Think You Are? (10 p.m., TLC): Christina Applegate learns about her family history.
Covert Affairs (10 p.m., USA): Annie tries to determine Teo’s true allegiances.
Suits (11 p.m., USA): Harvey’s client is arrested for murder.