While scuba-diving near shipwrecks off Bermuda, vacationing couple David Sanders (Nick Nolte) and Gail Berke (Jacqueline Bisset) recover a number of artifacts, including an ampoule of amber-colored liquid and a medallion bearing the image of a woman and the letters "S.C.O.P.N." (meaning "Santa Clara, ora pro nobis" or "Saint Clara, pray for us") and a date, 1714. Sanders and Berke seek the advice of lighthouse-keeper and treasure-hunter Romer Treece (Robert Shaw) on the origin of the medallion, who identifies the item as Spanish and takes an interest in the young couple. The ampoule is noticed by the man who had rented diving equipment to Sanders and Berke, which in turn attracts the attention of Henri 'Cloche' Bondurant (Louis Gossett, Jr.), a local drug kingpin for whom the shop owner works, who unsuccessfully tries to buy the ampoule and then begins to terrorize the couple with Haitian black magic. The ampoule contains medicinal morphine from the Goliath, a ship that sank during World War II with a cargo of munitions and medical supplies. The wreck of the Goliath is considered dangerous and is posted as off-limits to divers due to the danger of explosions. Treece concludes that a recent storm has exposed her cargo of morphine and unearthed a much older wreck containing Spanish treasure.
Treece makes a deal with Cloche, so they can dive in peace making him believe he will get the ampoules for a million dollars, while his real plan is to have the chance to find the treasure. Cloche gives him 3 days to recover them. Sanders, Berke, and Treece make several dives to the wrecks, recovering thousands of morphine ampoules from Goliath and several additional artifacts from the Spanish wreck. Adam Coffin (Eli Wallach), the only survivor from Goliath joins to help in the boat but his loyalty is not very clear when they get attacked by sharks and he only says "that he probably fell asleep" without noticing they were in trouble.
Through research in Treece's library, they reconstruct the history of the lost treasure ship, locate a list of valuable items, including a metallic jar with the letters "EF" engraved on it, and learn the identity of the noblewoman (Elizabeth Farnese) for whom they were made by the king of Spain. Sanders is determined to locate at least one item on the list to establish provenance; since without it there is no value to the treasure. Treece wishes to destroy the Goliath to put the morphine out of reach of Cloche; and Cloche interferes with their efforts so that he can recover the morphine for himself. During a running series of conflicts Treece's friend Kevin (Robert Tessier) is murdered by one of Cloche's henchmen and Adam betrays them and is killed when he triggers a booby-trap while trying to steal the recovered morphine. A climactic battle during the final dive ensues, with Cloche and his divers being killed in the destruction of the Goliath and the recovery of a gold dragon necklace that will provide the needed provenance of the treasure.
Where does David Sanders and Gail Berke take scuba-diving?
Near shipwrecks off Bermuda