Pidgin Island.

John Cranford is a U.S. customs agent dedicated to stem the activities of a gang of opium smugglers. After successfully closing the case, Cranford takes a vacation on Pidgin Island, near Kingston, Ontario. Here he meets the beautiful Diana Wynne, whose mysterious behavior both fascinates and attracts him. It turns out that Diana is herself a secret service agent, bent on trapping notorious pearl smuggler Michael Smeed.