One morning, a small mouse is swallowed whole by a hungry wolf. The mouse thinks this is the end, until he slides down into the wolf's belly and discovers something amazing. A cheerful duck is already living inside, and he has set up a lovely home complete with a dining table. It turns out that living inside a wolf is not bad at all. There are no chores, and you never have to worry about being eaten by other predators. The mouse and the duck become fast friends, enjoying fancy meals and throwing loud parties that give the poor wolf a terrible tummy ache. But when a hunter arrives in the forest, their peaceful life is threatened. The two friends must fight to protect the cozy home they have built inside the beast.