A briefcase with undisclosed contents – sought by Irish terrorists and the Russian mob – makes its way into criminals' hands. An Irish liaison assembles a squad of mercenaries, or 'ronin', and gives them the thorny task of recovering the case.

The absurd adventures of two defective detectives, who - despite unbelievable incompetence - somehow manage to solve their cases (or be nearby when the cases are solved) and retain their jobs.