Maurice Kline
Director
Gustav Della Valle
Director
Curt Siodmak
Screenplay
William D. Holmes
Screenplay
Don Megowan
Captain Fathom
Richard H. Cutting
Professor Barclay
Barbara Wilson
Carol Barclay
Kenneth Tobey
Jack Clyde
Rod Williams
Derek Taylor
David McMahon
Duncan
Robert Sampson
Gordon
David McLean
Seaman Duncan