8 p.m., FOXDeirdre Lovejoy)—a.k.a. the Gravedigger serial killer who the Jeffersonian team finally caught last season—finally goes on trial, but the team has a tough time finding evidence to convict her.
8:30 p.m., NBCRob Lowe and Adam Scott) to Pawnee to slash the department's budget. Ouch.
9 p.m., FOXAnna Torv) and Walter (John Noble) travel to the alternate universe to confront William Bell (Leonard Nimoy).
Season 5 finale, 9 p.m., CWJared Padalecki) and Dean (Jensen Ackles) deal with the Apocalypse and make life-changing decisions. I love summing up this show in two sentences.
9:30 p.m., NBCTina Fey) ex-boyfriends (guest stars Jon Hamm, Dean Winters, and Michael Sheen) return
12:35 a.m., CBS
Also on the airwaves...
FlashForward, 8 p.m., ABC
Survivor, 8 p.m., CBS
Community, 8 p.m., NBC
The Vampire Diaries, Season 1 finale, 8 p.m., CW
Grey's Anatomy, 9 p.m., ABC
CSI, 9 p.m., CBS
The Office, 9 p.m., NBC
Private Practice, Season 3 finale, 10 p.m., ABC
The Mentalist, 10 p.m., CBS
The Marriage Ref, 10 p.m., NBC
The Real Housewives of New York City, 10 p.m., BRAVO
NBA Basketball Playoffs: Cavaliers v. Celtics
What are you watching tonight?
Follow TV.com writer Stefanie Lee on Twitter: @StefAtTVDotCom