Joker and Hachi head for an island in the south seas to search for a clue to the Ancient Treasure, but the island turns out to be controlled by a clan of amazons who forbid the presence of men. After Hachi saves their leader, Tiger Mary, from a sticky situation, she immediately falls in love with him! When Hachi tries to run away from her, she traps him in the Vow of Love and Death, a jewel that can suck in anyone who responds to their name being called, and gets ready to force him to marry her!