While the Lyoko Warriors prepare to take advantage of a sunny afternoon, XANA launches an attack, sending them a polymorphic specter disguised as...them, constantly changing its appearance! Plus, not content with fighting unexpected specters at the school, our heroes are confronted with false avatars of themselves on Lyoko. Paranoia will soon settle in. And it's chaos on Lyoko as more false avatars keep showing up one after the other. (thetvdb.com)