William Lundigan

as Dr. Richard Donald Stanton

Herbert Marshall

as Dr. Donald L. Stanton / Narrator

Richard Carlson

as Dr. Jerry Lockwood

Martha Hyer

as Dr. Jane Flynn

Dawn Addams

as Susan Manners

Robert Karnes

as Walter Gordon

Lawrence Dobkin

as Dr. Delmar

George Eldredge

as Dr. Paul Dryden

Dan Riss

as Dr. Frank Werner

Michael Fox

as Dr. Klinger

King Donovan

as James O'Herli

Kem Dibbs

as David Wells

James Best

as Dr. Sidney K. Fuller