Hayley Mills

Character: Patti Randall

Dean Jones

Character: Zeke Kelso

Dorothy Provine

Character: Ingrid Randall

Roddy McDowall

Character: Gregory Benson

Frank Gorshin

Character: Iggy

Neville Brand

Character: Dan

Elsa Lanchester

Character: Mrs. MacDougall

William Demarest

Character: Mr. MacDougall

Richard Eastham

Character: Supervisor Newton

Grayson Hall

Character: Margaret Miller

Tom Lowell

Character: Canoe Henderson

Richard Deacon

Character: Drive-in-Manager

Iris Adrian

Character: Landlady

Liam Sullivan

Character: Graham

Don Dorrell

Character: Spires

Gene Blakely

Character: Cahill

Karl Held

Character: Kelly

Ed Wynn

Character: Mr. Hofstedder

Larry J. Blake

Character: Police Officer (uncredited)

John Cliff

Character: FBI Agent Hart (uncredited)

D.C. Benny

Character: Siamese Cat (uncredited)

Ben Lessy

Character: Drive-In Concessionaire (uncredited)