The carnival has come to Sequin—this is a party you don't want to miss!Trouble is brewing: Six of the Chaos Emeralds have disappeared without a trace, and Sonic and Tails are on the hunt for the seventh. They've tracked it to the intricate and opulent city of Sequin, where it's serving as the centerpiece of a citywide carnival.Sonic and Tails hope to catch the mysterious Emerald thief in the act, but they've got competition. Shadow and Rouge intend to claim the gem themselves, and they're not afraid to go through Sonic and Tails—or anyone else—to do it. Who will be the first to the Emerald? New faces, strange secrets, and plenty of adventure await!