Directed by Jack Arnold
Co-Director : W. Donn Hayes
Produced by William Alland
Written by Martin Berkeley
Story by Jack Arnold, Robert M. Fresco
Director of Photography : George Robinson
Music by Henry Mancini, Herman Stein
Film Editing by W. Donn Hayes, William M. Morgan
Art Director : Alexander Golitzen, Alfred Sweeney
Set Decorator : Russell A. Gausman, Ruby R. Levitt
Assistant Director : Frank Shaw
Make-Up Artist : Bud Westmore
Hair Stylist : Joan St. Oegger
Music Supervisor : Joseph Gershenson
Sound : Leslie I. Carey, Frank H. Wilkinson
Cast
John Agar (Doctor Matt Hastings)
Mara Corday (Stephanie 'Steve' Clayton)
Leo G. Carroll (Professor Gerald Deemer)
Nestor Paiva (Sheriff Jack Andrews)
Ross Elliott (Joe Burch)
Ed Rand (Lieutenant John Nolan)
Raymond Bailey (Dr. Townsend)
Hank Patterson (Josh)
Bert Holland (Barney Russell)
Steve Darrell (Andy Andersen)
Dee Carroll (Telephone Operator)
Edgar Dearing (Second Tramp)
Don Dillaway (Jim Bagny)
Clint Eastwood (Jet Squadron Leader)
Jane Howard (Coed Secretary)
James Hyland (Trooper Grayson)
Tom London (Jeff (1st Tramp))
Bob Nelson (State Trooper)
Eddie Parker (Paul Lund and Eric Jacobs as monsters)
Ray Quinn (State Trooper)
Vernon Rich (Ridley)
Bing Russell (Deputy)
Robert R. Stephenson (Warehouseman)
Jack Stoney (Helper)
Stuart Wade (Major Vernon)
Billy Wayne (Murphy)
Rusty Wescoatt (Driver)
Bud Wolfe (Bus Driver)