Jim Wormold is an expatriate Englishman living in pre-revolutionary Havana with his teenage daughter Milly. He owns a vacuum cleaner shop but isn’t very successful so he accepts an offer from Hawthorne of the British Secret Service to recruit a network of agents in Cuba.
| Actor | Role |
|---|---|
 Alec GuinnessJim Wormold | Jim Wormold |
 Burl IvesDr. Hasselbacher | Dr. Hasselbacher |
 Maureen O'HaraBeatrice Severn | Beatrice Severn |
 Ernie KovacsCaptain Segura | Captain Segura |
 Noël CowardHawthorne | Hawthorne |
 Ralph RichardsonC | C |
 Jo MorrowMilly Wormold | Milly Wormold |
 Grégoire AslanCifuentes | Cifuentes |
 Paul RogersHubert Carter | Hubert Carter |
 Raymond HuntleyGeneral | General |
 Ferdy MayneProfessor Sanchez | Professor Sanchez |
 Maurice DenhamAdmiral | Admiral |
| JJoseph G. PrietoLopez | Lopez |
 Duncan MacraeMacDougal | MacDougal |
| GGerik SchjelderupSvenson | Svenson |
 Hugh ManningOfficer | Officer |
 Karl StepanekDr. Braun | Dr. Braun |
 Maxine AudleyTeresa | Teresa |
| EElisabeth WelchWoman | Woman |
 Yvonne BuckinghamWoman | Woman |
 Rachel RobertsProstitute (uncredited) | Prostitute (uncredited) |
 John Le MesurierLouis (uncredited) | Louis (uncredited) |