The unthinkable has happened-Sin has dealt a crushing blow to Bucky Barnes, aka Captain America, unleashing her full fury on the Marvel Universe! With his country in flames, Steve Rogers enters the trenches, forcing the biggest decision of his entire life. And as the Marvel Universe hangs in the balance, Thor must finally confront The Serpent himself. Can the God of Thunder overcome the God of Fear, or will The Serpent prove that he is the one, true All-Father? The stakes have never been higher as the comic blockbuster event of the summer continues this July, only in FEAR ITSELF #4!