When Corporal Ray Charlton sets out to avenge the killing of his Platoon Commander by an IRA gunman in trouble torn Belfast, he unwittingly becomes a mere prawn swimming in the much deeper and murkier waters inhabited by MI5 agents; Double dealing informers, and a cabal of senior intelligence chiefs intent on a kill by any means policy, triggering a series of brutal events which Ray tries bury in his past, only to have them resurface three decades later with equally dramatic consequences.