It's spring break, and identical twins Elizabeth and Jessica Wakefield are taking a scuba diving course at Pirates Cove. On their first dive the twins discover the remains of an old pirate ship, and half a golden heart buried in the sand. Soon the twins receive spooky chain letters demanding that what was taken from the sea be returned. Jessica continues the chain; Elizabeth doesn't. Suddenly terrible things start happening to Elizabeth. She finds threatening notes in her room and a live scorpion in her lunch bag. Can Elizabeth discover the secret of the golden heart before the curse destroys her?