The Books of Truth - the collected prophecies of the mutant precog Destiny. In the wrong hands, the greatest threat to humanity ever known. For years guarded by Destiny's companion Mystique, most of the volumes are now in the possession of Professor Charles Xavier.
And therein lies the problem.
Fearing that absolute knowledge of the future would lead their mentor to a temptation the world could not afford, these X-Men exiled themselves from their home and teammates in order to hunt down the remaining Books of Truth, in the hope that they can locate the prophecies before Xavier - or someone worse - does.