- Play By:
- John Webster
- Broadcasting By:
- M. R. Ridley
- Production By:
- Felix Felton
- Monticelso a Cardinal (afterwardsPope Paul IV):
- Robert Farquharson
- Francisco de Medicis, Duke of Florence (Isabella's brother):
- Ronald Simpson
- Brachiano (otherwise Paulo Giordano Ursini Duke of Brachiano) husband of Isabella:
- Ralph Truman
- Giovanni, his son by Isabella:
- Peter Scott
- Lodovico an Italian Count:
- Russell Napier
- His friends:Antonelli:
- Ewen Solon
- His friends:Gasparo:
- Michael Hall
- Camillo, husband to Vittoria, and Monticelso's nephew:
- Godfrey Tudor
- Hortensio, one of Brachiano's officers:
- William Bridger
- Marcello, an attendant to the Duke of Florence and brother to Vittoria:
- Richard Baldwyn
- Flamineo his brother, and secretary to Brachiano:
- Geoffrey Wincott
- Julio a doctor:
- George Owen
- A lawyer:
- J Hubert Leslie
- Isabella, sister to the Duke of Florence, and wife to Brachiano:
- Heather Stannard
- Vittoria Corombona. a Venetian lady (first married to Camillo and afterwards to Brachiano):
- Sonia Dresdel
- Cornelia, mother to Vittoria,Flamineo,and Marcello:
- Sybil Thorndike
- Zanche a Negress, servant to Vittoria:
- Maria Barry
- Matron of the House of Convertites:
- Nora Nicholson
- Narrator:
- Ian Cooper
