William Powell as Nick Charles

Myrna Loy as Nora Charles

Keenan Wynn as Clarence "Clinker" Krause

Dean Stockwell as Nick Charles Jr.

Phillip Reed as Tommy Drake

Patricia Morison as Phyllis Talbin

Leon Ames as Mitchell Talbin

Gloria Grahame as Fran Page

Jayne Meadows as Janet Thayar

Ralph Morgan as David Thayar

Bess Flowers as Jessica Thayar

Don Taylor as Buddy Hollis

Warner Anderson as Dr. Monolaw

Bruce Cowling as Phil Brant

Connie Gilchrist as Bertha

Henry Nemo as The Neem

William Bishop as Al Amboy

Marie Windsor as Helen Amboy

Morris Ankrum as Inspector (uncredited)

James Burke as Policeman Callahan (uncredited)

Tom Dugan as Policeman Davis (uncredited)

James Flavin as Policeman Reardon (uncredited)

Esther Howard as Sadie (uncredited)

Clinton Sundberg as Mr. Purdy (uncredited)

Asta Jr. as Asta (uncredited)