"When Oliver, Mya, and Jorge take a ride in a hot-air balloon, they crash-land on an unknown island filled with extinct animals and a horde of angry Vikings. Welcome to Poptropica, an uncharted group of islands whose existence is hidden from the rest of the world. As the three friends embark on a perilous search for a way home, they discover that something sinister is lurking on the island--something that threatens the very existence of Poptropica itself!"--Back cover.