In Singapore, a private detective and the British authorities are on the trail of a crime syndicate that kidnaps a nuclear physicist with the aim of selling him to the highest bidder.
| Actor | Role |
|---|---|
 Dan DuryeaMike Callahan / Corrigan | Mike Callahan / Corrigan |
 Gene LockhartAlexis Pederas | Alexis Pederas |
 Patric KnowlesJulian March | Julian March |
 Reginald DennyMajor Ian Bone | Major Ian Bone |
 Nigel BruceGovernor Sir Charles Coutts | Governor Sir Charles Coutts |
 Marian CarrFrennessey March | Frennessey March |
 Arthur ShieldsSean O'Connor | Sean O'Connor |
 Douglass DumbrilleInsp. McCollum | Insp. McCollum |
| CCarmen D'AntonioDancer | Dancer |
 Keye LukeWong | Wong |
 Clarence LungJohnny Chan | Johnny Chan |
| LLou NovaGuzik | Guzik |
 Patrick AllenNot listed | Not listed |
| SSpencer ChanNot listed | Not listed |
| HHerschel GrahamClub Patron (uncredited) | Club Patron (uncredited) |
| SStuart HallMilitary Officer (uncredited) | Military Officer (uncredited) |
| GGeorge HoaglandNot listed | Not listed |
| GGustave LaxNot listed | Not listed |
 Strother MartinNot listed | Not listed |
| BBeal WongNot listed | Not listed |