Already living in a society that mistrusts them, the mutants are faced with even more discrimination after an unforeseen enemy - who may be a mutant with extraordinary powers - launches a devastating attack. The news of the assault causes a public outcry against the mutants, including renewed support for the Mutant Registration Act, and William Stryker, a military leader rumored to have experimented on mutants (possibly including Wolverine), is among the most vocal supporters of the legislation. Stryker puts into motion a plan to eradicate the mutants and begins an offensive on the X-Men mansion and school. Magneto, having escaped from his plastic prison, forms an unlikely alliance with Professor Xavier to stop Stryker. Meanwhile, Wolverine heads north to investigate his past.