ToonGully: The Last Rainforest is a parody of FernGully: The Last Rainforest that stars Suki Higurashi from the Universe XP Kingdom Hearts series as Crysta and Ash Ketchum as Zak Young, along with Mushu as they protect the rainforest from Lord Dr. Nightmare (Jim Cummings), also from Universe XP Kingdom Hearts series as Hexxus.
The film tells the story of ToonGully, a rainforest in Neverland. A curious fairy girl named Suki Higurashi (Willa Holland) and her fairy friends (Sora, Kairi, Ai, Rukia Kuchiki, Rocky the Flying Squrriel, Yakko, Wakko and Dot) saw a part of the world she and her friends never seen before beyond ToonGully and believes humans dwell on the nearby mountain Mount Warning. But the wise sprite of the forest and Crysta's motherly figure, Kaede (Pam Hyatt), says humans are now extinct. In the opening scene, she says that they fled, driven away by the attack of an enemy known as Lord Dr. Nightmare (Attorney at Law), the spirit of destruction and all that is toxic to nature, never to return and presumed dead; Nightmare was defeated by the fairies and imprisoned inside a tree. Suki mentions a black cloud that she saw rising near the mountain, and Kaede identifies it as smoke, but nervously dismisses Suki's speculation that the smoke might be Nightmare, saying "There isn't a force in nature that could release him, and there are no poisons here on which he can feed. Nightmare is trapped for all time." It is implied that Kaede shares Suki's fears, but is afraid to say so openly.
Befriending a mentally unstable yet comical Chinese Dragon named Mushu (Eddie Murphy) who has been experimented on by humans and now has wires and antennas fused into his head, Suki heads to Mount Warning where she finds dead trees all marked with red aerosol paint crosses, which mark them for cutting. She finds male humans, and accidentally shrinks one named Ash Ketchum in trying to prevent him from being crushed by a tree. He gets stuck on a spiderweb on the tree that's just about to go through a tree shredder. She tries to get him off but can't when Mushu swoops in, grabs them both off of the spiderweb and blames Suki and her friends for them almost getting killed, because they did not listen to him.
Ash (Veronica Taylor) goes on a wild adventure with Suki and Mushu, nearly getting eaten by a hungry tiger named Dagnino (Crispin Freeman), and unexpectedly falls in love with Suki. Meanwhile, Ash's superiors cut down an enchanted baobab tree that Ash had accidentally painted an X mark on while trying to spray a fly that was buzzing around him. Unfortunately, this turns out to be the tree Nightmare is trapped in, and the cutting down and processing of the tree by the lumbermill-like leveler machine releases him. Determined to get revenge upon the fairies of ToonGully (specifically Kaede) for imprisoning him, Nightmare apparently gains power from the pollution, specifically the energy and smoke produced by the Leveler, as he can be seen "drinking" from it like a liquid. He manipulates the lumberjacks and their tree leveler into tearing down the rainforest in the direction of the fairies by the next morning, thereby destroying the very fabric of their world. He does this under the vocal guise of their boss.
Up until this point, all the fairies have not had a clue as to what danger awaits them. That is until Ash tells the truth about who he is and what the humans are doing in ToonGully.
Once the truth is revealed the fairies all join forces and fuse their powers together, creating a protective tree cage. Kaede sacrifices herself (giving her power to the fairies and even Ash) and it is up to Suki and the other fairies to defeat Nightmare. Ash turns off the leveler, causing Nightmare to lose all the energy he was gaining from it and disappear, but he soon rips out of the machine as a giant demonic skeleton bear creature made of oil that breathes fire. Suki seemingly sacrifices herself like Magi did by allowing Nightmare to devour her in one bite, and uses her powers from inside him to grow a seed she had with her to again imprison Nightmare (together with the leveler) inside a new tree with help from the fairies led by Marco Bellies the White Jellie Bear fairy (Reno Wilson), thereby imprisoning him again. However, she emerges, unharmed and alive, from a flower soon after. Suki sadly resizes Ash to normal size and he sets off with his fellow lumberjacks, Brock and Tai, to try to stop the destruction of the rainforests. Meanwhile, Suki takes Kaede's place after learning finally how to control her powers.
- Eddie Murphy reprises his role of Mushu in this parody (you wish)
- Dagnino from Noah's Ark/El Arca will be voiced by Crispin Freeman in this parody
- Somebody actually remembered the film "Ferngully: The Last Rainforest"