FernGully: The Last Rainforest is a 1992 Australian animated film directed by Bill Kroyer, produced by Peter Faiman and Wayne Young, and written by Jim Cox based on a book of the same name by Diana Young. It is a film with a strong environmental theme. The film features the voice talents of Jonathan Ward as Zak, Samantha Mathis as Crysta, Tim Curry as Hexxus, Robin Williams as Batty Koda, and Christian Slater as Pips.
Crysta is a fairy with a curious nature living in FernGully, a pristine rainforest free from humans. The fairies of FernGully once lived in harmony with humans, but believe them to have gone extinct after being driven away by a malevolent spirit named Hexxus. Crysta is the apprentice of Magi, a motherly-figure fairy who imprisoned Hexxus in a tree. One day Crysta explores a new part of the forest and meets Batty, a bat who claims to have been experimented on by humans, giving him an unstable personality. She refuses to believe him until she encounters lumberjacks cutting down trees. She sees Zak, a young human who is about to be crushed by a tree, and Crysta accidentally shrinks him, though does not know how to restore him to normal size.
The tree that Hexxus is imprisoned in is cut down by Tony and Ralph, Zak's superiors. Hexxus quickly begins to regain his powers by feeding on pollution. He manipulates the humans to drive to FernGully. In FernGully, Zak meets Pips, a fairy male who is jealous of Zak's relationship with Crysta. Zak begins to fall for Crysta, but hides the true reason that the humans had returned. When the signs of Hexxus' resurrection begin to manifest themselves in poisoned trees and rivers, he admits that humans are destroying the forest. The fairies mount an attempt to defend their homes, but knowing their fight is hopeless, Zak convinces Batty to aid him in stopping the machine before it destroys them. When Zak makes his presence known to his bosses, Hexxus takes over the machine and begins to wildly destroy the forest.
Magi sacrifices herself in order to give the fairies a chance, and she tells Crysta to remember everything she's learned. Zak manages to stop the machine, seemingly killing Hexxus by stopping his power at the source, but he manifests himself within the oil in the machine and begins to ignite the forest ablaze. Crysta seemingly sacrifices herself by allowing herself to be devoured by Hexxus and all seems lost, until he begins to sprout limbs and leaves like a tree. Pips and the rest of the fairies rally to the powers they have been given, which causes the seed that Crysta fed him to start growing wildly. Hexxus is made dormant and turned into a twisted tree at the very border of FernGully. Crysta appears after the fight, having survived her ordeal and successfully succeeded Magi as a magical fairy. She gives Zak a seed, begging him to remember everything that has transpired and she sadly restores him to his human size. Remembering the seed in his hand, Zak promises to remember his adventure, and buries the seed in the soil before telling his superiors that things "gotta change" before leaving the forest with them. The seed sprouts new growth for Ferngully, as Crysta follows Pips with Batty behind her.