Young and innocent fairy Crysta (voice of Samatha Mathis), who calls the rainforest of Ferngully her home, rescues human Zak (voice of Jonathan Ward) from an out of control logging machine by shrinking him down to fairy size. Unfortunately, she is unable to return him to his own size, and Zak ends up involved in a fight not only against the loggers who are deforesting Ferngully, but also against the evil Hexxus (voice of Tim Curry), who the loggers accidentally free from the tree where he is imprisoned.