Jayce wanted an adventurous summer, but he's pretty sure that's not going to happen when he and his twin sister, Terri, are sent to see their grandfather. His name is Theodore Hunter III, and Jayce doesn't know anything about him, except that he owns some fancy island resort off the coast of California. His mom won't tell him much else.
When they arrive at Theo's island, it doesn't look very fancy, and Jayce is prepared to spend the summer bored out of his mind-until he meets Livia, who shares his adventurous streak. Terri and Jayce soon make friends with other kids who work on the island, too, Zack and Emmett, and things appear to be looking up for a summer of fun.
But the island hides secrets, which slowly reveal themselves to the twins. Jayce finds a curious oval piece of silver with strange writing, and so begins a journey of enchantment. The island is filled with mysteries, and it's up to a ragtag group of teenagers to uncover Theo's secrets-and the secrets of the beautiful paradise they now call home.