Vengeance of the Deep (1923)

Captain Musgrove, the brutal lord of a South Sea island, prevents the natives from participating in his pearl-diving enterprise. When Tagu, son of the native chief, is penalized by the captain for poaching, he avenges himself by attempting to kill Frederico, Musgrove's chief diver. Although Frederico is determined to marry the captain's daughter, Ethel, she prefers a beachcomber named Jean. During an experimental dive, Jean and Frederico discover a treasure chest and decide to conceal their find from Musgrove. However, as they return to shore, Frederico abandons Jean when he is trapped by a giant clam. As Frederico is about to marry Ethel, Jean emerges from the ocean and punishes his rival. Jean wins Ethel and becomes the new chief diver.