Strange fumes sicken all of the Avengers - save for Iron Man, whose suit of armor provides him with protection. Now the armored Avenger must race against time to synthesize a cure for the infected - while the team face the prospect of being quarantined by U.S. Defense Secretary Dell Rusk, who has sent Doc Samson, Falcon, the Red Hulk and the Winter Soldier to arrest them. When Captain America is captured by the Winter Soldier and brought before Dell Rusk, he learns that the enigmatic Secretary harbors a diabolical secret from the supersoldier's past.