"When the shadowwalkers were victorious in their battle against the Ant Queen, they hoped their work to save Caldera was done. But the rainforest has begun to rumble. Rumi, a scholarly tree frog who can control the wind, must bring his band of animal friends to face the greatest danger they've yet encountered--the giant volcano beneath the jungle itself. While the volcano roars, rumors of a mysterious evil blanket Caldera--the Elemental of Darkness...