Kevin McCarthy as Dr. Miles J. Bennell

Dana Wynter as Becky Driscoll

King Donovan as Jack Belicec

Carolyn Jones as Theodora 'Teddy' Belicec

Larry Gates as Dr. Dan 'Danny' Kauffman

Kenneth Patterson as Stanley Driscoll

Virginia Christine as Wilma Lentz

Jean Willes as Nurse Sally Withers

Ralph Dumke as Police Chief Nick Grivett

Guy Way as Officer Sam Janzek

Bobby Clark as Jimmy Grimaldi

Beatrice Maude as Grandma Grimaldi

Whit Bissell as Emergency Room Psychiatrist

Richard Deacon as Emergency Room Doctor

Robert Osterloh as Ambulance Attendant

Guy Rennie as Restaurant Owner

Eileen Stevens as Anne Grimaldi

Tom Fadden as Uncle Ira Lentz

Jean Andren as Eleda Lentz

Everett Glass as Dr. Ed Pursey

Sam Peckinpah as Charlie the Meter Reader

Dabbs Greer as Mack Lomax

Marie Selland as Martha Lomax

Harry J. Vejar as Man carrying pods in Mile's office (extra)

J. Pat O'Malley as Railroad Baggage Handler (extra)