Hurricane Smith (John Ireland) and his marooned sailors escape from a South Seas island by stealing the ship of Capt. Raikes (Emile Meyer) who's come to the island in search of slaves. Smith sails the ship to Australia where he charters it to two individuals who claim to be studying flora and fauna. To fill out his crew, Smith "shanghais" Capt. Raikes who, by this time, has also made his way to Australia. During the course of the voyage, it becomes clear that their passengers are actually in search of a cache of gold that's been hidden on a South Seas island. Smith also seeks this gold, which he considers his own, as does Capt. Raikes. Complicating this 3-way rivalry is a growing shipboard romance between Smith and the beautiful Luana (Yvonne De Carlo). Events reach a violent climax when the treasure-island is finally reached.