Jet, leader of the thieving Babylon Rogues, observes the Key to Babylon Garden, an artifact and family heirloom said to unlock the secrets of their Babylonian ancestors. Doctor Eggman arrives and claims he can use the Chaos Emeralds to make Babylon Garden rise, asking for the Rogues' help in retrieving them. The Rogues agree and steal an Emerald, but run into Sonic, Tails, and Knuckles, who are also looking for the Emerald. Sonic gives chase, but Jet escapes with the Emerald. The next day, the three heroes see Eggman on a digital billboard advertising an Extreme Gear race known as the World Grand Prix, with the Chaos Emeralds offered as the grand prize. When they realize that the Rogues are participating, Sonic and his friends enter as well.