In this time of global anxiety, economic turmoil and mass hysteria, Sin, the new Red Skull, has made an awesome discovery...a shameful secret that will rock the foundations of the Marvel Unverse! A revelation that will divide father and son, turn friend against friend, and herals the rise of Fear personified. Who is the Serpent? As Odin and the Asgardians leave the Earth to fend for itself, the Avengers and the world's remaining heroes battle the unstoppable avatars of his evil? And how can the Avengers respond...to fear itself? The Mighty Thor--imprisoned by his own father! Steve Rogers makes the decision of a lifetime when a hero falls! And Iron Man makes the ultimate sacrifice. Matt Fraction and Stuart Immonen bring fans the biggest Marvel event since CIVIL WAR!