The serial is set on a remote island in the Caribbean, where reporter Larry Kent (Don Terry) and his enemies search for a lost treasure trove of gold. Kent arrives on the island in search of another reporter who had gone missing. Kent discovers that valuable lost treasure is buried on the island, and finds half of a map which holds a clue to its location. Toni Morrell (Gwen Gaze), the daughter of a shipmate whose murdered partner knew where the treasure was buried, agrees to help Kent investigate his friend’s disappearance and locate the treasure. Morrell and Kent are opposed by a villain named Collins (Walter Miller) who uses his henchmen and supply of weapons and land mines in an attempt to stop them. Kent’s enemy in the film is Dr. X. (Hobart Bosworth) who wears a skull mask and pirate clothing, and is in the process of developing a powerful explosive. Due to the actions of Dr. X., Kent is nearly buried alive, killed with dynamite and slashed in a sword battle. He defeats Dr. X. in the last installment of the serial titled “Justice”.