Four adventurers descend to the bottom of the sea. When their surface tether snaps, they find themselves marooned in a network of underwater caverns.
Prof. Millard Wyman
Craig Randall
Dale Marshall
Paul Whitmore
Lauri Talbott
Dr. J.R. Matheny
Old Man in the Caverns
Jim Wyman
Wilson, Sonar Man
The Captain
Hank
Reporter
Jimmy, Reporter
Narrator