This new high-speed adventure's plot depends on which team you choose. Team Sonic (Sonic, Tails and Knuckles) get a letter from Eggman saying that they only have 72 hours until Eggman unleashes his new and improved Metal Sonic doomsday device on the world. Meanwhile, Rouge is flying around and finds Shadow (yes, he's back!) and E-123 Omega capsulized. Omega is furious that Eggman disposed of him, and Shadow is rendered of all memory, and he wants after Eggman to find out what really happened to himself. Thus, Team Dark is made. Amy reads about Sonic going after Eggman in the newspaper. Amy is mad at Sonic because she wasn't brought along. Big The Cat is once again on the lookout for his frog Froggy, and Cream The Rabbit is looking for Chocolate, Cream's Chao's twin. Here comes Team Rose! Team Chaotix (Vector, Espio, and Charmy) has formed a detective agency and has been offered a huge pay if they investigate a mysterious case. Vector sees this as an opportunity to outsmart Eggman and .