Extraordinary X-Men versus Uncanny Inhumans! The X-Men have just learned that the Terrigen Mist - the source of the Inhumans' powers, which, through a cruel twist of fate, just happens to be lethal to mutants - has reached an irreversible saturation point. Earth is on the verge of being rendered uninhabitable to their kind. And now they see no other option than to strike against the Inhumans to ensure their own survival. But one X-Man doesn't take the decision lightly. Storm has literally led her team through hell and back, but will she command them in battle against their longtime friends and allies?
