It's the end of the world. A flood is coming. For Dave a few awkward Nestrians, and his son Finny, an Ark has been built to save all animals. But as it turns out, Nestrians aren't allowed. Sneaking with her daughter Leah, two Grymps and the help of Hazel aboard, they think that they're safe. Before curious kids fall off the Ark.. Now turn the Ark around and make an effort to reach the surface of a mountain, even while Hazel and Dave must reserve their differences, Leah and Finny struggle to survive the flood and starving predators and save their kiddies. It's not at all going to be smooth sailing.