"A scientist develops a formula which will cause animals to regress to the form of their primitive ancestors, and tries it on himself with disastrous results."
Robert Shayne
as Prof. Clifford Groves
Richard Crane
as Dr. Ross Harkness
Joyce Terry
as Jan Groves
Doris Merrick
as Ruth Marshall
Robert Long
as Game Warden George Oakes
Tandra Quinn
as Celia
Beverly Garland
as Nola Mason, bar waitress
Dick Rich
as Sheriff Andy Andrews
Lee Morgan
as Charlie Webb, bar owner
Frank Gerstle
as Mr. Wheeler, hunter
Robert Easton
as Danny, a townsman
Eric Colmar
as Buck Hastings, a townsman
Robert Bray
as Jim Newcomb, a townsman
Anthony Jochim
as Skeptical Naturalist
Marshall Bradford
as Naturalists' Conference Chairman
William Fawcett
as Dr. Fairchild
Tom Monroe
as Thickset Townsman at Webb's Cafe
Ann Staunton
as State Trooper Dispatcher
Walter Koestler
Art Direction
Aubrey Wisberg
Writer
Stanley Cortez
Director of Photography
Jack Pollexfen
Fred R. Feitshans Jr.
Editor
Producer
E.A. Dupont
Director
Albert Glasser
Original Music Composer
Ilse Lahn
Associate Producer
Harry Thomas
Makeup Artist