Characters played by Hugh Marlowe
Dr. Russell A. Marvin
Characters played by Joan Taylor
Carol Marvin
Characters played by Donald Curtis
Maj. Huglin
Characters played by Morris Ankrum
Brig. Gen. John Hanley
Characters played by John Zaremba
Prof. Kanter
Characters played by Thomas Browne Henry
Vice Adm. Enright
Characters played by Grandon Rhodes
Gen. Edmunds
Characters played by Larry J. Blake
Motorcycle Cop
Characters played by Fred Aldrich
Airplane Passenger
Air Intelligence Command Officer
Man in Saucer Attack
Characters played by Nicky Blair
Military Officer at Experiment
Characters played by Jimmy Cross
Military Messenger
Characters played by Jack Deery
Military Officer
Characters played by Charles Evans
Dr. Alberts
Characters played by Raoul Freeman
Military Official
Characters played by Paul Frees
Alien
Characters played by James Gonzalez
Military Official
Characters played by Duke Green
Minor Role
Characters played by Ed Haskett
Military Official
Characters played by Clark Howat
Sgt. Nash
Characters played by Harry Lauter
Cutting - Generator Technician
Characters played by Don Marlowe
Minor Role
Characters played by William Meader
Worker in Control Tower
Characters played by Sol Murgi
Plane Passenger
Characters played by Forbes Murray
Military Officer at Experiment
Characters played by William J. O'Brien
Radio Listener
Characters played by Murray Pollack
Plane Passenger
Characters played by Mike Ragan
Tank Commander
Characters played by Alan Reynolds
Maj. Kimberly
Characters played by Bert Stevens
Air Intelligence Command Officer
Characters played by Arthur Tovey
Officer
Civilian at Military Conference
Characters played by Dale Van Sickel
Man Crushed Beneath Wall
Characters played by Guy Way
Civilian Observing Saucer Attack
Characters played by Bob Whitney
Plane Passenger
Characters played by Frank Wilcox
Alfred Cassidy
Characters played by Beal Wong
Chinese Radio Listener
Characters played by William Woodson
Narrator