The gold bug (1980)

Shortly after the Civil War, while exploring the long deserted and reputedly haunted Sullivan's Island off Charleston S.C., a boy encounters two obsessed eccentrics living there. These men chase him away and warn him never to return or to tell anyone about them. Soon, however, they locate him and summon him back, because he has unknowingly given them a clue vital to their quest and they need his help to unravel the rest of the mystery. If he can do so, they will find buried pirate treasure and all become rich. But in joining the search, he falls under the same obsession and curse -- an ominous fate suggested by the unearthly electronic music which contributes to the film's atmosphere.