The story is set in Harbor's End, an old fishing port town on the U.S. East Coast perpetually shrouded in sea fog, in the present day. Ostensibly a quiet fishing community, the town has in fact been dominated by the Halston family's shadowy wealth and power for 26 years—they control everything from the docks and fishing licenses to the police station and city hall. Thirty nautical miles off the town's coast lies a stretch of water called "Trident Reef", where an ancient legend of a sea god's temple is said to open once every 300 years on a full moon. Jaxon Reed, a former Navy SEAL, returns to his hometown, only to witness his fiancée's betrayal the second he steps through his front door, his father's inherited fishing boat being forcibly impounded, and his mother being sent to a nursing home—while the real conspiracy begins to surface with the first Spanish gold coin pulled from a sunken ship on the seabed.
