The Sweeney - Season 4 Episode 8 -

A wealthy entrepreneur is being blackmailed over activities he performed whilst stationed as a soldier in Malaya. He seeks assistance from two other former soldiers who had been involved, one of whom is now a senior police officer, the other now a security company owner/manager. The policeman attempts to stop Inspector Regan from investigating. The security company man hires mercenaries to persuade the blackmailers to desist.