- Author/Adapted by:
- Margaret Potter
- Producer:
- Trevor Hill
- Old Mr Poppleton, the antique dealer:
- Herbert Smith
- The children - Elizabeth:
- Gabrielle O' Mahoney
- The children - Peter:
- John Thornley
- Sam, a youth:
- Martin Ewart
- 'Jock' Tulliver, his chum:
- David Webster
- Captain John Doyle:
- Graham Tennant
- Edwards, First Mate on the Saucy Jane:
- Frank Poynter
- The Organ-Grinder:
- Geoffrey Banks
- Colonel Von Reibnitz, Hamburg Chief of Police:
- David Mahlowe
- Lieutenant Weissman, his assistant:
- Christopher Dyer
- A river pilot:
- David Crane
- A young German boy:
- Michael Stirrup
- Jack Hargreaves, a member of the Foreign Press Association:
- Ronald Baddiley