Rod Taylor

as Peter McDermott

Catherine Spaak

as Jeanne Rochefort

Karl Malden

as Keycase Milne

Melvyn Douglas

as Warren Trent

Merle Oberon

as The Duchess Caroline

Richard Conte

as Detective Dupere

Michael Rennie

as Geoffrey - Duke of Lanbourne

Kevin McCarthy

as Curtis O'Keefe

Carmen McRae

as Christine

Alfred Ryder

as Capt. Yolles

Roy Roberts

as Bailey

Al Checco

as Herbie Chandler

Sheila Bromley

as Mrs. Grandin

Harry Hickox

as Sam

William Lanteau

as Mason

Ken Lynch

as Joe Laswell

Clinton Sundberg

as Lawrence Morgan

Tol Avery

as Kilbrick

Davis Roberts

as Dr. Elmo Adams

George Boyce

as Bellhop

Charles Alvin Bell

as Vickery

Robert Goodwin

as Henry

Jack Donner

as Elliott (uncredited)

Lester Dorr

as Cy - Elevator Operator (uncredited)

Vince Howard

as Tousaint (uncredited)

Dorothy Konrad

as Housekeeper (uncredited)

Judy Norton

as Daughter (uncredited)

John Sebastian

as Giotti (uncredited)

William Swan

as Young Desk Clerk (uncredited)

Arthur Tovey

as Hotel Patron (uncredited)

Ivan Bonar

as Silverstein (uncredited)

Wilma Francis

as Woman at Airport

Dee Carroll

as Mother (uncredited)