Thomas F. Wilson
Ed Klingbottom
Karim Prince
Roy Dubro
M. Emmet Walsh
Stanley
Brion James
Air Force
Wigald Boning
Dr. Strangemeister
Ben Stein
Men in Strangemeister's Head
George Kennedy
Army
Donna D'Errico
Press Secretary
Barry Bostwick
President Smith
Rodger Halston
Glaxxon
Don Stroud
Old Bob
John Bishop
G-Man
Patricia Elliott
Girl Scout Leader
Melissa Rivers
Female Reporter #1
Dave Fennoy
Glaxxon (voice)
Dee Bradley Baker
Subordinate Alien (voice)
Jennifer Coolidge
Charles Philip Moore
Alien #1
Amy Kidd
Female Reporter #2
Blaine Etcheverry
Male Reporter
Lacey Taylor Robbins
Girl Scout
Michael McDonald
Secret Service Agent
Manny Fernandez
Paul Di Franco
General Pandemonium
Carlos Bernard
Alien
Rob Kerchner
Lifeguard
Preston Ahearn
Danny Mann
Alien #1 (voice)
Susan Silo
Alien #2 (voice)
Bobby Edner
Michael Reardon
Spock
Mary Ann Schmidt
Bikini Girl
Seth Bailey
John Wayne Gacy's 'Pogo the Clown' (uncredited)
Rob Paulsen
Dr. Strangemeister (voice) (uncredited)