Dennis Price

Louis Mazzini / His Father

Alec Guinness

The D'Ascoyne Family: The Duke / The Banker / The Parson / The General / The Admiral / Young Ascoyne / Young Henry / Lady Agatha

Joan Greenwood

Sibella

Valerie Hobson

Edith D'Ascoyne

Audrey Fildes

Mama

Miles Malleson

The Hangman

Clive Morton

The Prison Governor

John Penrose

Lionel Holland

Cecil Ramage

Crown Counsel

Hugh Griffith

Lord High Steward

John Salew

Mr. Perkins

Eric Messiter

Inspector Burgoyne

Lyn Evans

The Farmer

Barbara Leake

The Schoolmistress

Peggy Ann Clifford

Maud Redpole

Anne Valery

The Girl in the Punt

Arthur Lowe

The Reporter

Peter Gawthorne

First Lord Delivering Verdict (uncredited)

Molly Hamley-Clifford

Lady Redpole (uncredited)

Leslie Handford

Gamekeeper Hoskins (uncredited)

Cavan Malone

Young Graham (uncredited)

Jeremy Spenser

Young Louis (uncredited)

Carol White

Young Sibella (uncredited)

Laurence Naismith

Warder in Jail (uncredited)

Gordon Phillott

Clerk of Parliament (uncredited)

Richard Wattis

Defence Counsel (uncredited)

Harold Young

Captain (uncredited)