Danger and action abound after Akira Sengoku and his classmates crashland on a deserted island while flying home from a class trip. The island doesn't exist on any maps but that's not even the strangest part: the animals they find on the island are prehistoric beasts that are supposed to have been extinct for thousands of years! Now Akira and his friends are in danger as the island's residents start eyeing the humans for their next meal. Will they ever solve the mystery of the island and find their way home?
After learning that the island they’re on may be near Okinawa, Sengoku and his friends put a plan in motion to sail back to Japan. But before they can do that, a decision is made to check our the fourth and final tower on the island. Their journey into the depths of this mysterious structure is sure to result in many discoveries, but then they least expect it, they may also find that they’re not the only ones in the building…