Jamaica Run (movie, 1953)

Promoter William Montague wants to buy the estate owned by the Daceys, Mrs. Dacey and her daughter Ena and son Todd, in order to build a resort hotel. When they turn him down, he produces a couple of distant relatives, Janice and Robert Clayton, and sets about to prove that the estate rightfully belongs to them. The identity of the rightful heirs is thought to be buried in a sunken ship off of the Jamaican shore and the search begins, led by a schooner skipper, Patrick Fairlie, who is in love with Ena.