- Writer:
- Francis Durbridge
- Producer:
- Martyn C. Webster
- Paul Temple:
- Peter Coke
- Steve:
- Marjorie Westbury
- Herr Breckshaft:
- Jeffrey Segal
- Mrs Weldon:
- Virginia Winter
- June:
- June Tobin
- Denis Harper:
- John Bryming
- Elliot France:
- James Thomason
- Elsa, Countess Dekker:
- Joan Matheson
- Dr Conrad:
- Rolf Lefebvre
- Joyce Gunter:
- Dorothy Smith
- Fritz Gunter:
- George Hagan
- Other parts played by:
- Beatrice Ormonde
- Other parts played by:
- John Graham
- Other parts played by:
- Judy Bailey
- Other parts played by:
- John Hollas
