On what was Magneto's island base, Illyana Rasputin gets called away into a strange building and disappears. Kitty Pryde follows. Not coming back, the X-Men go looking for her. And suddenly they all find themselves in Limbo. Generally alone, they encounter alternate versions of each other, including old corpses of their friends. Kitty is captured by Belasco and forced to watch as Illyana begins receiving instruction from him. The other X-Men encounter and fight S'ym. Finally the X-Men fight Belasco, and defeat him with an older Storm's help. Kitty rescues Illyana, and they return to our world, but Illyana is now 13 years old!