Lee Van Cleef
Dr. Tom Anderson
Beverly Garland
Claire Anderson
Peter Graves
Dr. Paul Nelson
Sally Fraser
Joan Nelson
Russ Bender
General James Pattick
Jonathan Haze
Pvt. Miguel Ortiz
Dick Miller
Sgt. Neil
Paul Harbor
Floyd Mason
Charles B. Griffith
Dr. Pete Shelton
Karen Kadler
Ellen Peters
Taggart Casey
Sheriff N.J. Shallert
Thomas E. Jackson
George Haskell
Marshall Bradford
U.S. Secretary Platt
David McMahon
Gen. Carpenter
Paul Blaisdell
The Monster (uncredited)