Fringe, 30 Rock, and Supernatural

8 p.m., FOX


Heather Taffet (Deirdre 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., NBC

Parks and Recreation

The state department sends two auditors (guest stars Rob Lowe and Adam Scott) to Pawnee to slash the department's budget. Ouch.

9 p.m., FOX


In the first part of the two-part Season 2 finale, Olivia (Anna Torv) and Walter (John Noble) travel to the alternate universe to confront William Bell (Leonard Nimoy).

Season 5 finale, 9 p.m., CW


As season 5 comes to a close, so does the world. Sam (Jared 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., NBC

30 Rock

As promised, Liz's (Tina Fey) ex-boyfriends (guest stars Jon Hamm, Dean Winters, and Michael Sheen) return for May sweeps... to attend Floyd's (Jason Sudeikis) wedding? Sure. Plus, Tracy (Tracy Morgan) continues his quest for an EGOT.

12:35 a.m., CBS

The Late Late Show with Craig Ferguson

Craig welcomes Iron Man 2 star Robert Downey Jr. and writer Dave Barry.

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 writer Stefanie Lee on Twitter: @StefAtTVDotCom

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