Disaster at sea! When the yacht "Helsinor" strikes a reef in the Lesser Antilles, the passengers take to a lifeboat. Upon their return to the United States, accusations fly. Did one of the survivors drug the others and pitch the millionaire owner of the yacht, Lawrence Thacker, into shark-infested waters? Lt. Valcour begins an informal investigation. When one of the heirs to the Thacker millions is poisoned, Valcour's investigation becomes official. Of course, the logical thing to do is to gather the survivors aboard the "Helsinor II" and return to the scene of the original wreck...

The Lesser Antilles Case is is the 7th Lt. Valcour novel.