HMS Truculent is a nuclear-powered, hunter-killer submarine, and one of the most deadly weapon systems in the world. Phil Hitchens is its distinguished British commander - who has broken away from a NATO exerise and embarked on his own darkly vengeful and deadly mission.Shadowhunt is the codename of the desperate sonar searcher for HMS Truculent, last seen heading for the kola Inlet where the cream of Soviet sea power lies unsuspecting at anchor.