Jonah is fourteen and lives in a small community on the East Coast in 1958. He and his best friend, Beaz, have figured out a way to get to the forbidden Oak Island to seek treasure. They find a gold locket down one of the treasure shafts and can't believe their luck-until they realize that the locket is not pirate's booty but possibly evidence in a current murder investigation, one which Jonah already knows more about than he can handle. Beaz is in danger from his abusive mother if she finds out he's gone to Oak Island, so Jonah keeps the secret even though there is a killer at large in his small community.