Donald Grant as Richard Clark

Denise DuBarry as Professor Diane Bennett

Henry Gibson as Dr. Philip Pennyworth

Paul Walker as 'Professor' Bennett

Claude Akins as Sheriff Sam Ketchem

Howard Duff as Father Martin Finnegan

Donald Moffat as General Franklin Turnbull

Paul Dooley as Roy Crane

John Carradine as Old Joe Shempter

Frank Ashmore as Scoop Johnson

Stella Stevens as Margo Crane

Fergie as Lucy

Kevin Peter Hall as The Monster

Kenneth Kessler as Voice

Jesse White as Ben

Ritchie Montgomery as Deputy Spiro

James Arone as Soldier

Benny Baker as Mr. McGinty

Doc Duhame as Deputy Conner

Arthur Taxier as Television Newscaster

Clare Torao as Television Newscaster

Brad Kesten as Rex

Evan Arnold as Beaver

Corky Pigeon as Danny