In an effort to make amends for his past in weapons manufacturing, Tony Stark has dedicated himself to building the world up rather than tearing it down. Traveling to Japan to build a new arc reactor that will deliver unlimited free energy to the Japanese people, Stark is challenged by the Japanese government and the media when he attempts to import the necessary nuclear priming device.  When the nuclear reactor is repeatedly attacked by the mysterious Zodiac consortium, Stark must gather his allies to take on Zodiac and its mastermind.