Sonic Chaos, is an American comedy-action film, and is unconnected to Sonic the Hedgehog the Movie or the video game for Sega Game Gear and Master System. This movie marks the only appearance of Cherise LaGlide, a character who is reminiscent of Rouge the Bat.
The film starts at camp with Amy teaching Tails how to dance. Sonic says that Professor Caninestein wants them to come to his laboratory, which they do and the professor shows them the message he received from his cousin, Professor Inu, who is an Akita breed of dog. The transmission tells them that all his appliances have gone rogue, since a menacing, egg-shaped man has programmed all his devices for evil. The heroes agree to help him and stop Robotnik from getting his hands on all the high-end technology to enslave the planet. So they all head off in Tails' plane. They fly by Angel Island, and pick up Knuckles on the way, who wonders what they're up to. They tell him about what happened, and at first, he is skeptical, but then it turns out he somehow agreed to go with them, or at least realized that they're already on another adventure anyway.
Professor Inu, welcomes the heroes on the landing strip of the building his lab is in, and says he will reimburse them for places to stay. His laboratory is now barren, due to his appliances running away from him. Left at a loose end, the heroes can do nothing more than go with Tails and Amy's desire to enjoy the place as tourists. Tails goes to an "all-you-can-eat" sushi bar, where his bottomless appetite quickly rouses the ire of the chefs. (Second time his appetite is referenced in this way since "Too Tall Tails").
Sonic and Amy, meanwhile, visit a video game arcade, where Sonic's game skills attract a lot of attention, especially that of a cute girl, who introduces herself as Cherise LaGlide. Amy, jealous and miffed leaves the arcade where she sings out her feelings in a Karaoke bar ("I'll Never Fall in Love Again"). It turns out, when Sonic comes to Tails' aid, when the fox boy was being attacked by a food processor, that Robotnik has been using Chaos Emerald Power to power up the appliances.
Meanwhile, Knuckles finds a warehouse where he overhears a conversation between Robotnik's badniks, Scratch and Grounder about a secret weapon before being caught. Robotnik arrives and also catches him, and to get out of the situation, Knuckles offers them 1/7th of the Chaos Emeralds if he doesn't unleash his secret weapon.
In the room that they are staying in, Cherise tries to swipe more of the Chaos Emeralds from the heroes, and she just barely gets caught by Knuckles. The next day, the gang, with Amy being reluctant - due to her still being upset with Sonic- vows to find more of the Chaos Emeralds that are powering up appliances with negative energy. They are sure they found one on top of a hill, and they are pursued by more evil appliances on the way. Cherise finds them, and compliments Sonic more on his heroism, and kisses him. Amy is infuriated by this, but Robotnik and his badniks appear, Cherise is revealed to be an agent of his, and the chaos emerald turns out to be a fake. The badniks apprehend all the heroes and lock them up in the prison of his flying fortress. Tails feels bad and thinks it was a bad idea to go sight-seeing. But Knuckles confesses that he made a bargain with Robotnik, which the others, of course, find that was a low move, but he tells them at the time, it didn't seem like a bad idea. So then the heroes trick Scratch and Grounder, who got a recent promotion to guard bots for catching the heroes, into letting them free. They rush towards where the source of power to charge Robotnik's secret weapon is, a central electric tower. The city is in panic, so the citizens tried to get to safe places while chaos ensues. They find out the secret weapon is an updated version of Metal Sonic. A battle takes place, but just as they think they've won, Metal Sonic assumes a new transformation, which seems like it will put up more of a fight. After Amy and Knuckles get the Chaos Emerald from Cherise, who swiped it from them earlier, and Amy tosses it to Sonic, who uses the complete set to transform into Super Sonic.
After winning the battle, the citizens congratulate them with a celebration the next day. After being thanked personally by Professor Inu, Tails asks if he has any family in the Latin part of Mobius, and everyone stares at him.