Captain Markham charters the boat of the evil Captain Blackton to search for a treasure he once buried on a South Sea island. Accompanying him are his daughter, Lois, and first mate Steve Maitland. They arrive at the island in time to witness a native ceremony of choosing the Fire Bride for sacrifice to the gods. Blackton accompanies Markham to the island to search for the gold, kills him when they find it, and reports to Lois and Steve that they were attacked by natives. Blackton goes ashore to bury Markham but incurs the natives' wrath when he dishonors Atel, the Fire Bride. Steve warns Blackton but, when he learns that the villain caused the death of his sister, helps the natives subdue him.