What's New Tonight: Thursday, May 2nd.

8:00 PM EST:

“American Idol” on FOX. Elimination episode. One of the final four is sent home. Featuring a performance by David Cook.

“Community” on NBC. Chang plots to destroy Greendale. Abed finds that the lives of the study group members have been intertwined for years.

“The Big Bang Theory” on CBS. Sheldon is overly excited when he hires Professor Proton (guest star Bob Newhart), the host of his favorite TV show when he was a kid, to visit the apartment. Howard and Bernadette agree to dogsit for Raj, but things go haywire.

“The Vampire Diaries” on The CW. Stefan and Damon try to get Elena to act more humanely, but their approach seems a little brutal. Caroline has a dangerous encounter with Klaus. Bonnie grows suspicious of Katherine when she makes an offer that allegedly benefits them both.

9:00 PM EST:

“Beauty and the Beast” on the CW.

“Glee” on FOX. The New Directions perform hits by Stevie Wonder. Artie gets news that may affect his future. Rachel prepares for her callback on “Funny Girl”.

“Grey’s Anatomy” on ABC. Bailey refuses the help from her colleagues. Owen worries about Ethan, thinking he may end up in foster care. A craniofacial specialist helps out a young patient. A magician’s assistant gets hurt during a magic trick.

10:00 PM EST:

“Elementary” on CBS. Sebastian Moran informs Sherlock that his nemesis Moriarty may be responsible for a string of recent murders, including a man thought to have died from natural causes.

“Hannibal” on NBC. A new copycat murderer stumps Jack. Dr. Chilton thinks he may have the Chesapeake Ripper in custody. Jack reaches out to Hannibal to deal with his grief.

“Scandal” on ABC. Surprising revelations occur when they investigate for the mole. Fitz wants Jake to look out for Olivia. Mellie’s actions force Cyrus to deal with a crisis.