| Fred Emney |
Dr. Septimus Jankers |
| Cardew Robinson (as Cardew 'The Cad' Robinson) |
Cardew Robinson |
| Vera Day |
Maisie |
| Johnny Brandon |
Fanshaw |
| Davy Kaye |
Ferdy |
| Freddie Mills |
Harry The Scar |
| Gerald Campion (as Gerald (Billy Bunter) Campion) |
Fatty Gilbert |
| Miriam Karlin |
Mildred M. Mainforce, The Private Eye |
| Kynaston Reeves |
Mc. Tavish |
| Gabrielle Brune |
Matron |
| Claude Hulbert |
Mr. Winkle |
| Paul Daneman |
Fred Fudge - The Porter |
| Roger Avon |
Ferdinand Walter Ethelred Horsetrough |
| Ronnie Corbett (as Ronald Corbett) |
Chumleigh |
| Aud Johansen |
Mlle. Praline |
| Stanley Unwin |
Tate & Lyle Guide |
| Douglas Ives |
1st Keeper |
| Neil Wilson |
2nd Keeper |
| Tom Gill |
Constable |
| Stuart Saunders |
Station Sergeant |
| Dino Galvani |
Prof. Stromboli |
| Peter Butterworth |
The Potter |
| Francis Langford's Singing Scholars |
Boys |
