Bela Lugosi
Boroff
Ralph Byrd
Lt. Terry Kent
Maxine Doyle
Jean Norman
Richard Alexander
Thorg
Lee Ford
Snapper McGee
Herbert Rawlinson
Cmdr. Boyle
John Picorri
G.A. Rackerby [Chs. 2-12]
Allen Connor
Dick Norman
Thomas Carr
Ens. Jim Kent [Ch. 1]
Lawrence Grant
Rabinisi - Boroff's Spokesman at Screening [Ch. 1]
Carleton Young
Henchman Dodds [Ch. 4]
George Chesebro
L.H. Degado - Chief Thug [Ch. 5]
Ranny Weeks
Wies - Ambulance Orderly Thug [Ch. 4]