Kareem Abdul-Jabbar, Kevin Smith And William Shatner Guest Star On An All-New 'The Big Bang Theory'

The Big Bang Theory returns with an all-new episode tonight at 8:00 PM ET/PT, only on CBS. Tonight's episode features a litany of guests stars including Joe Manganiello, Kevin Smith, Kareem Abdul-Jabbar and the show's great white whale - William Shatner.

Check out the clip above for a behind-the-scenes look at the series' latest episode and be sure to tune in tonight to see Leonard, Sheldon, Penny and the gang mix it up on screen with these massive stars. Check you local listings for more information.