 Dirk BogardeMelville Farr | Melville Farr |
 Sylvia SymsLaura Farr | Laura Farr |
 Dennis PriceCalloway | Calloway |
 Anthony NichollsLord Charles Fullbrook | Lord Charles Fullbrook |
 Peter CopleyPaul Mandrake | Paul Mandrake |
 Norman BirdHarold Doe | Harold Doe |
 Peter McEneryJack Barrett | Jack Barrett |
 Donald ChurchillEddy Stone | Eddy Stone |
 Derren NesbittSandy | Sandy |
 John BarrieInspector Harris | Inspector Harris |
 John CairneyBridie | Bridie |
 Alan MacNaughtanScott Hankin | Scott Hankin |
 Nigel StockPhip | Phip |
| FFrank PettittBarman (as Frank Pettit) | Barman (as Frank Pettit) |
 Mavis VilliersMadge | Madge |
 Charles Lloyd PackHenry | Henry |
 Hilton EdwardsP.H. | P.H. |
| MMargaret DiamondMiss Benham | Miss Benham |
| DDavid EvansMickey | Mickey |
 Noel HowlettPatterson | Patterson |
 Alan HowardFrank | Frank |
| DDawn BeretSylvie | Sylvie |
 Frank ThorntonGeorge - Henry's Assistant (uncredited) | George - Henry's Assistant (uncredited) |
 John BennettUndercover Detective (uncredited) | Undercover Detective (uncredited) |
 Basil DignamBarrister (uncredited) | Barrister (uncredited) |
 Jim BradyTransport Cafe Patron (uncredited) | Transport Cafe Patron (uncredited) |
| JJack TaylorBuilding Site Foreman (uncredited) | Building Site Foreman (uncredited) |
 Nora GordonFarr's Housekeeper (uncredited) | Farr's Housekeeper (uncredited) |
