Many events and adventures happened to Sonic and his friends. Defeating Dr. Robotnik and his army, saving Statishion Square, saving the Earth from space colony ARK and defeating Shadow, defeating Metal Sonic, and a bunch of other adventures... Now the heroes are located where they were born - the planet Mobius. Even there, the heroes face problems in the face of the Doctor. Robotnik, but they are successfully coping with it. But this time... Even Sonic won't be saved...