The Biker Mice are trapped in Detroit. Their old archenemies Limburger and Napoleon Brie are planning to conquer Chicago with the Regenerator and the aliens in their custody. In addition, our heroes have other things to worry about: Has Stoker switched sides? Meanwhile Charley and Carbine are searching for the Biker Mice, but they meet an unknown mouse from Stoker's past....his daughter Spitfire.
