Ep 11. The Ghost and Mr. Martin

Zack and Cody's favorite uncle, Uncle Martin, comes for a visit. As soon as he see's London's expensive blue sapphire necklace, he tells a tale. He believes that when someone wears a blue sapphire necklace in the Caribbean sea at sundown, they are to awaken a ghost. The ghost is then to haunt those who have seen, purchased, touched or even thought about the necklace. The only survivors are those who dwell on land. Since the entire gang is far from land, they all believe they are doomed.