The young dinosaurs find a mysterious island and Chomper returns to the hidden valley.

"You have spent your whole life hiking and exploring an island in Lake Champlain, not far from your home. One weekend, you and your friend Jayme decide to make a trip out to the island. Her anxieties about the weather grow more realistic and you lose control of the Zodiac, your boat...The storm has brought a lot of strange things with it--the moment you step ashore, you and Jayme feel it. You don't know how, but you're certain the island has taken...