Flash Gordon (archive footage)
Buster Crabbe
Dale Arden (archive footage)
Jean Rogers
Prof. Henson (archive footage)
George Cleveland
The High Priest (archive footage)
Lon Poff
Atom Furnace supervisor (archive footage)
Charles McMurphy
Priest #2 (archive footage)
Theodore Lorch
(scenes deleted) (archive footage) (as Duke York Jr.)
Duke York
Transcontinental airplane pilot (archive footage) (uncredited)
Lynton Brent
Telescreen monitor (archive footage) (uncredited)
Al Ferguson
Robot / Ming soldier (archive footage) (uncredited)
Fred Kohler Jr.
Monkey-Man (archive footage) (uncredited)
Bull Montana
Constantine Romanoff
Dr. Hans Zarkov (archive footage)
Frank Shannon
Robot / Ming soldier / Gocko (archive footage) (uncredited)
Glenn Strange
Captured soldier (archive footage) (uncredited)
Harry Wilson
Ming the Merciless (archive footage)
Charles Middleton
Princess Aura (archive footage)
Priscilla Lawson
Prince Barin (archive footage)
Richard Alexander
King Vultan (archive footage)
Jack 'Tiny' Lipson
Prince Thun (archive footage)
James Pierce
Officer Torch (archive footage)
Earl Askam
Prof. Gordon (archive footage)
Richard Tucker
Director
Frederick Stephani
Ray Taylor
Writer
Ella O'Neill
George H. Plympton
Basil Dickey
Story
Alex Raymond
Original Story