Ken Morgan
Robert Lowery
Prof. Ernst
George Macready
First Cop with Thor
Charles King
Police Inspector Hamilton
Kenneth MacDonald
Mason
Bud Osborne
Thor
Ray Corrigan
Prof. Marsden
John Elliott
Zoo Guard
Kit Guard
Prof. Franklin Arnold
Ralph Morgan
Babs Arnold
Carole Mathews
Flash
Willie Best
Dick Nordik
Jack Ingram
Joe Flint
Anthony Warde
Joe Butler
Ted Mapes
Blake
Eddie Parker
Mead
Stanley Price
Stunts
Director
Howard Bretherton
Music
Lee Zahler
Screenplay
Sherman L. Lowe
Editor
Dwight Caldwell
Royal K. Cole
Earl Turner
Director of Photography
L. William O'Connell