- Louis Jourdan
- Duke Philippe de Beauvais
- Belinda Lee
- Virginia Traill
- Keith Michell
- Colonel St. Gerard
- Richard O'Sullivan
- Louis XVII / Richard de Beauvais
- Martita Hunt
- Lady Lydia Fell
- Finlay Currie
- Mr. Patient
- Anne Heywood
- Glynis
- Brian Rawlinson
- Dylan Evans
- Terence Longdon
- Col. Sir Frederick Venner
- Frederick Leister
- Capt. Andrew Ogden
- Derek Oldham
- William
- Jean Mercure
- Chief of Police
- Raymond Gérôme
- Citizen-Director of the Revolution
- Austin Trevor
- M. Petitval
- Jean Claudio
- DeCastres, Philippe's Comrade in Paris
- Laurence Payne
- Lautrec
- Jacques B. Brunius
- De Chassagne
- Richard Clarke
- (uncredited)
- John Dearth
- Simon the Jailer
- Sam Kydd
- (uncredited)
- Lisa Lee
- Simon's Wife
- André Mikhelson
- Prison Doctor Perrot
- Anthony Sadler
- Minor Role
- Margaret Sawyer
- French Child
