In a village far away, deep in a valley, all the animals and birds disappeared some years ago. Only the rebellious young teacher and an old man talk about animals to the children, who have never seen such (mythical) creatures.

Otherwise there's a strange silence round the whole subject. One wretched, little boy has dreams of animals, begins to whoop like an owl, is regarded as an outcast, and eventually disappears. A stubborn, brave girl called Maya and her friend Matti, are drawn to explore in the woods round the village.

They know there are dangers beyond and that at night, Nehi the Mountain Demon comes down to the village. In a far-off cave, they come upon the vanished boy, content and self-sufficient. Eventually they find themselves in a beautiful garden paradise full of every kind of animal, bird and fish - the home of Nehi the Mountain Demon. The Demon is a pied piper figure who stole the animals from the village.

He, too, was once a boy there, but he was different, mocked and reviled, treated as an outsider and outcast. This is his terrible revenge, one which has punished him too, by removing him from society and friendship, and every few years he draws another child or two to join him in his fortress Eden, where he has trained the sheep to lie down with the wolves, and where predators are few. He lets the two children return to the village, telling them that one day, when people are less cruel and his desire for vengeance has crumbled, perhaps the animals might come back...