Henry and Emmy's American friends John and Margaret Colville are happily excited when he takes early retirement and they decide to buy an inn on the Caribbean island of St. Matthew's in the British Seaward Islands. This island is relatively undeveloped, except for the Golf Club, where the wealthy American and British visitors can stay, and avoid the riffraff.
But when one of the visitors at the Golf Club is murdered, apparently by an islander, tensions escalate between the locals and the tourists. The Governor sends an SOS to Scotland Yard, and Henry is dispatched to investigate. Emmy comes too, and they stay with the Colvilles at their inn. As Henry tries to discover what really happened and why, violence breaks out following the arrest — against his advice — of a local agitator. How Henry eventually untangles the various threads makes for a very interesting story. Recommended.