Adaptation of Robert Louis Stevenson's novel about an adventure on the high seas that leaves three men stranded on an island. Captain Chisholm, Swanson and Bunch find themselves thrown together in a Caribbean hell-hole. The three are starving, bedraggled and wracked by tropical fevers. When a plague ship arrives in the bay, its flag warning of the threat of smallpox, it looks as if they have found a way out. The consul needs a crew to sail the boat to Australia, a crew desperate enough to ignore the threat of disease. Once at sea, the discovery of the contents of the cargo pits the crew against each other and forces Captain Chisholm to face up to his personal demons. A storm throws the three men into another kind of hell, an unchartered island ruled by a man called Ellstrom.