Rob Corddry as Gary Supernova (voice)

Brendan Fraser as Scorch Supernova (voice)

Jessica Alba as Lena (voice)

Steve Zahn as Hawk (voice)

Sarah Jessica Parker as Kira Supernova (voice)

Ricky Gervais as Mr Bing (voice)

Gregg Binkley as Ralph (voice) (uncredited)

Sofía Vergara as Gabby (voice)

Kaitlin Olson as 3D Movie Girl (voice)

Ashley Eckstein as Alien (voice)

Craig Robinson as Doc (voice)

Jane Lynch as Io (voice)

George Lopez as Thurman (voice)

Jonathan Morgan Heit as Kip Supernova (voice)

Chris Parnell as Hammer (voice)

William Shatner as General Shanker (voice)

Bob Bergen as 3D Movie Guy (voice)

Joshua Rush as Young Shanker (voice)

Doug Abrahams as Hazmat / Baabian Citizen (voice)

Sean Kenin as Radio Host (voice)

Bill Hader as Announcer (voice) (uncredited)