The X-Men face their most formidable and powerful enemy, one of them is Jean Gray. During a rescue mission in space, Jean almost lost his life when it is struck by a mysterious cosmic force. Once back home, this force not only makes it infinitely more powerful, but much more unstable. Struggling with this entity inside her, Jean frees his powers in ways that can neither understand nor contain. With this power out of control, Jean will hurt the people he loves most,