Ordered to take over a Knox-class frigate from an alcoholic skipper, Dan finds he's inherited a damaged ship, an untrustworthy crew, and an ambiguous mission. He is to take USS Oliver C. Gaddis, soon to become PNS Tughril, on her final voyage to be donated to Pakistan. But in Karachi, Dan gets new orders: take Gaddis still further east, and operate against modern pirates preying on commercial shipping in the remote, dangerous South China Sea.
Pursing an elusive and shadowy foe into an exotic, isolated world of hazardous reefs and tropic islands, Dan gradually discerns a larger purpose behind his supposed objective. Who are these "pirates?" What expansionist cunning supports them? Abandoned by the Navy, threatened by a mutinous crew, a murderous shipmate, and an approaching typhoon, Gaddis struggles to survive without crossing the shadow-line herself.