Rex Harrison

Cecil Fox

Susan Hayward

Mrs. Sheridan

Cliff Robertson

William McFly

Capucine

Princess Dominique

Edie Adams

Merle McGill

Maggie Smith

Sarah Watkins

Adolfo Celi

Inspector Rizzi

Hugh Manning

Volpone

David Dodimead

Mosca

Mimmo Poli

Cook (uncredited)

Luigi Scavran

Massimo (uncredited)

Jack Benny

Violinist Outside Restaurant (uncredited)

Herschel Bernardi

Oscar Ludwig (uncredited) (scenes deleted)

Massimo Serato

The Pretender (uncredited) (scenes deleted)

Joseph L. Mankiewicz