Naomi and Nick are staying the night with their friends Sam and Lucy when they hear the sound of someone crying coming from far away. They all begin to investigate, and soon find a light coming from beneath the floor under Sam's bed, and a ladder leading down into a very curious mist. As they descend the ladder, the children find themselves amongst many tall dark trees, and Sam and Naomi know they have returned to the magic rainforest.
This time there are new problems to solve, and some old friends to help find solutions. But there are some old enemies too, who will do anything to cause mischief!