When his mother eloped with an Italian opera singer, Louis Mazzini was cut off from her aristocratic family. After the family refuses to let her be buried in the family mausoleum, Louis avenges his mother's death by attempting to murder every family member who stands between himself and the family fortune. But when he finds himself torn between his longtime love and the widow of one of his victims, his plans go awry.
Dennis Price
as Louis Mazzini / His Father
Alec Guinness
as The D'Ascoyne Family: The Duke / The Banker / The Parson / The General / The Admiral / Young Ascoyne / Young Henry / Lady Agatha
Joan Greenwood
as Sibella
Valerie Hobson
as Edith D'Ascoyne
Audrey Fildes
as Mama
Miles Malleson
as The Hangman
Clive Morton
as The Prison Governor
John Penrose
as Lionel Holland
Cecil Ramage
as Crown Counsel
Hugh Griffith
as Lord High Steward
John Salew
as Mr. Perkins
Eric Messiter
as Inspector Burgoyne
