This is the season finale, so don't be surprised if there's some sort of cliffhanger.
Elsewhere on TV ...
Missing (7 p.m., ABC/Ch. 4): Dax learns who his enemies are.
Community (7 p.m., NBC/Ch. 5): Abed is convinced that Dean Pelton is an imposter.
American Idol (7 p.m., Fox/Ch. 13): Another hopeful is eliminated.
The Vampire Diaries (7 p.m., CW/Ch. 30): Jeremy makes a life-changing decision. (Season finale)
30 Rock (7:30 p.m., NBC/Ch. 5): Avery is back, and Jack is suspicious.
Person of Interest (8 p.m., CBS/Ch. 2): Reese learns something about Finch's past.
Grey's Anatomy (8 p.m., ABC/Ch. 4): The residents decide where they're going to work.
The Office (8 p.m., NBC/Ch. 5): A former boss helps Andy mount a coup. (Season finale)
Touch (8 p.m., Fox/Ch. 13): Martin tries to expose a corrupt parole officer.
The Secret Circle (8 p.m., CW/Ch. 30): Jake, Melissa and Adam try to save Faye from the witch hunters. (Season finale)
Parks and Recreation (8:30 p.m., NBC/Ch. 5): Leslie awaits the election results. (Season finale)
The Mentalist (9 p.m., CBS/Ch. 2): Jan gets a message from Red John.
Scandal (9 p.m., ABC/Ch. 4): A series of flashbacks show how Olivia came to work for the president and how she later assembled her team.
Awake (9 p.m., NBC/Ch. 5): An unusual dream disrupts Britten's ability to switch realities.