Paul Duggan, aged 11, lives in tiny, rural Darkfield on the borders of the beautiful and mysterious wetlands, known as the Callows. Strange planes are seen flying over the village, and a mining company starts buying up the land to turn it into an open-cast mine. Only old, eccentric Magpie O'Brien opposes the mining. Paul must find the courage to stand up to the school bullies and to this new threat to his way of life. Will the mine bring wealth and happiness, as the villagers hope -- or ruin and death?