This movie starts off with Rosellia recalling about meeting Sophia Hans, the mayor of Ficuton. She was a very evil person who wanted to rule the world. Rosellia also said that she heard that Sophia is teaming up with Jimmy McCartney and two other cities: Electronica and Hippoville to take over Wilcoxton and use their tallest tower, Christie Plaza and Jimmy McCartney's Jupiter Scope to destroy the real world as we know it. So the team decided to go to Wilcoxton and stop Sophia's plan once and for all. Along the way, they meet The Cheetahmen:
- Chris: The Leader of the group who has super strength.
- Scarlett: The Athlete of the group who has telekinesis and acrobatic skills.
- Tom: The Scientist of the group who has power constructs.
- Anna: The Beauty of the group who has a double-bladed sword that she can throw at enemies.
- Seth: The Comedian of the group who has a big bow and arrows.
- Zoe: The Little Girl of the group who has fire manipulation.
They also meet Lillia Katherine, a human girl who has fur on her skin with a fluffy tail and superpowers such as transforming herself into a cat, shooting beams of fire out of her hands and doing acrobatics and agility. They also have to defeat Demon Alice, a devilish version of Alice who is much stronger. She was also a part of this plan, too.
- Kayla as Sophie the Otter, Gamora, Jelly Otter, Pamela Jackley, Mimi Rabbit, Dotty Dog, Butterbear, Rainbow Brite, Kai-Lan, Gadget Hackwrench, Ashley Evergreen, Suzie Squirrel, and Lillia Katherine
- Kimberly as Peanut Otter, Roobear Koala, Grover Chestnut, Bobby Bear, Zipper Cat, Dr. Myiesha McStuffins and Potato Chip Popple
- Princess as Bonnie Wagner, Canary Yellow, Selena Maxson, Lulu and Woolma Lamb
- Shy Girl as Baby Butter Otter, Roxie Raccoon, Pretty Bit Popple, Shy Violet, Bibsy Popple, and Mingle
- Tween Girl as Pinch Raccoon, Pancake Popple, Ricky Rabbit, and Laura Koala
- Emma as Indigo
- Kate as Lala Orange, Aunt Nanner, Doc McStuffins and Party Popple
- Catherine as Hallie
- Belle as Pamie Penguin, Sheriff Callie, Patty O'Green and Anna
- Julie as Bootsie Snootie, Penny Pig, Prize Popple, Puffball Popple, Betty Koala, and Mommy Koala
- Grace as Scarlett
- Allison as Hoppopotamus
- Jennifer as Sophia Hans
- Ivy as Rosellia, Melody, Twink, Scootch Raccoon, Lambie, Cribsy Popple, Portia Porcupine, Patty Rabbit, Chip, Dale, and Zoe
- Salli as Alice/Demon Alice and Fanny Fox
- Zack as Kiwi, Colt Kangaroo, Mikey Mole, Hoho and Moosel
- Eric as Star-Lord, Horsey Kangaroo, and P.C. Popple
- Alan as Chris, Starlite, Drax the Destroyer and Monterey Jack
- Brian as Ootsie Snootie, Buddy Blue, and Donny McStuffins
- Dave as WilliamWill2343, Groot, Toby and Weather
- Young Guy as Billy Wagner, Rusty Wildwood, Red Butler, Flick Duck, Nick Penguin, Deputy Peck, Bingo "Bet-it-All" Beaver, Zipper, Rintoo, Tolee, Stuffy and Seth
- Diesel as Papa Koala, Marcus McStuffins, and Chilly
- Paul as Jimmy McCartney, Rocket Raccoon, Bumblelion, Ernest Otter, and Tom
- Duncan as Yeye
- Wise Guy as Putter Popple
- Professor as Puzzle Popple and Walter Kangaroo
Development for the film began in June 2014, roughly a year before the film released in theaters. Officer Squidward was trying to find a plot for his movie, Adventures of Officer Squidward Movie, but couldn't find a good story in time for his interview with the distributor, Columbia Pictures. They quickly declined the project and Officer Squidward abandoned it. On December 12, WilliamWill2343 saw some potential storylines for the film. He renamed it The WilliamWill Movie. WilliamWill wants to finance his own projects. He talked about a hundred project deal with OddLot Entertainment or DreamWorks Pictures, but he quickly finds OddLot Entertainment a much more accurate choice. They accepted the deal. He wrote a story that features some characters from the Action GameMaster Universe. On January 1, 2015, PB&J Otter were the first ones to join the cast of characters in the film. In January 5, the film was green-lighted by WilliamWill Pictures.