Iron Man and Captain America are two core members of the Avengers, the world's greatest superhero team. But when a tragic battle blows a hole in the city of Stamford, killing hundreds of people, the US government demands that all superheroes unmask and register their powers. To Tony Stark - Iron Man - it's a regrettable but necessary step. To Captain America, it's an unbearable assault on civil liberties.

While visiting Japan, Wolverine is recruited to recover a stolen experimental drug, one that has the potential to be a true miracle cure for all human disease - or a sadistic means of enslaving the world. With every hour bringing mankind closer to tragedy, he embarks on a daring mission to identify the thieves and thwart their terrifying agenda.

The X-Men are mutants—born with extraordinary powers that set them apart from the very humanity they are sworn to protect. Now, groundbreaking research has revealed a method for reversing the genetic mutation responsible for mutant powers—whether the mutant wants it reversed or not. The US government wants to use this procedure to eliminate the so-called mutant menace once and for all—but the X-Men soon learn that the true source of the procedure is their old enemy, Sinister! And his agenda is far more complex and dangerous than even the X-Men can imagine.

The fate of the entire Marvel Universe hangs in the balance as Earth's mightiest heroes face their greatest challenge! Summoned across the stars by the mysterious and unbelievably powerful Beyonder, the Avengers, Spider-Man, the Fantastic Four, and the X-Men are set against their deadliest foes on the mysterious planet known as Battleworld - with the winner promised the ultimate prize. But as battle lines are drawn, new alliances are forged, and old enemies clash, one among them is not willing to settle for anything less than godhood.

The sequel to The Present and the conclusion of the Time's Arrow trilogy narrates the struggle of the X-Men and Spider-Man to stop the time-traveling madman Kang the Conqueror from destroying the multiverse and time as they know it.