Errol Willow is not an ordinary boy. He is a Treeman - a person who has control over trees. He thinks he is alone in his part of the world until he finds out that a girl named Alison Juniper is a flowerman. Suddenly mortals start disappearing. A nightman who calls himself The Black Night is behind it. Errol and Alison have to stop him before he gains world dominance, and destroys all life...