On screen
Cast
14 credited performers
John Carradine
Prof. Millard Wyman
Robert Clarke
Craig Randall
Phyllis Coates
Dale Marshall
Artwork unavailable
Allen Windsor
Paul Whitmore
Sheila Noonan
Lauri Talbott
George Skaff
Dr. J.R. Matheny
Artwork unavailable
Maurice Bernard
Old Man in the Caverns
Artwork unavailable
Joe Maierhouser
Jim Wyman
Lloyd Nelson
Wilson, Sonar Man
Artwork unavailable
Harry Raven
The Captain
Artwork unavailable
Milt Collion
Hank
Artwork unavailable
Lowell Hopkins
Reporter
Artwork unavailable
Jack Haffner
Jimmy, Reporter
Artwork unavailable
Robert Carroll
Narrator