Hercules’ Caribbean vacation is interrupted by unseasonal snow. Investigating, Hercules hitches a ride with the US Navy while Titan’s computer, ISAAC, converses with Vision about Maelstrom’s recent death, until Hercules radios to alert them to the growing weather problem. Thor arrives and explains that the Casket of Ancient Winters has been opened, threatening to plunge the world into a new Ice Age. As the demonic Sons of Muspell invade New York, the Avengers meet their rampage. Unable to contact the West Coast Avengers or Alpha Flight, Vision finally reaches Mr. Fantastic, who sends himself, She-Hulk ,and the Human Torch to the Avengers’ aid just as numerous Asgardians arrive as well to repel the demons, and Hercules parachutes in from a Navy jet. Elsewhere, Deathurge welcomes a reborn Maelstrom, who begins plotting anew. In Manhattan, the battle seems almost over until the sky darkens as a new demon wave arrives.