The X-Men face their most formidable and powerful foe when one of their own, Jean Grey, starts to spiral out of control. During a rescue mission in outer space, Jean is nearly killed when she's hit by a mysterious cosmic force. Once she returns home, this force not only makes her infinitely more powerful, but far more unstable. The X-Men must now band together to save her soul and battle aliens that want to use Grey's new abilities to rule the galaxy. Jean Grey begins to develop incredible powers that corrupt and turn her into a Dark Phoenix, causing the X-Men to decide if her life is worth more than all of humanity. + More