There are six different species of alien living on the massive ark that arrives at Earth, settling into orbit around Mars. Onnusabi, Balnicot, Etati, Pauravan, Ruffinati, and Cundisent. While they retain their own cultures and beliefs, they all live together peacefully, and their mission is to explore the universe and share their cultures in peace. But they all share strangely similar myths, and the stories tell of terrible destruction; Planet Eaters and Destroyers of Worlds that ride on the mouths of serpents leaving Armageddon in their wake. The aliens said they came in peace. But who really knows for sure? Lots of humans don’t trust them. Some think they’re probably here to eat us. When Mitzi’s parents got jobs on the giant spaceship, she became the only human kid in a classroom full of weird creatures with tentacles and inside-out mouths. But despite their differences, she’s made three new friends: Boxtop, Angel, and Flemm. And she really wants to believe they like humans as much as they say they do. So when she discovers that all alien cultures share a common myth about giant serpents who destroy planets and wipe out civilizations, she’s determined to find out if the stories have any basis in truth. Maybe they’re just stories. Or maybe, she’ll need to help humanity prepare for the end of the world.