One week: That was all the time given to the X-Men to correct a universe-threatening flaw after it was discovered that unknown forces had severely altered the structure of the heroes' home dimension. It hadn't taken them long to track down the source of the disruption: the tyrannical Doctor Doom, in possession of the Cosmic Cube -- a device that allows its owner to twist reality and create their personal vision of a perfect world. But now their old enemy Magneto has the Cube, and the danger has only gotten worse...