Metal Gear Solid 2 revolves around the "Big Shell", a massive offshore clean-up facility that has been seized by a group of terrorists that call themselves "Sons of Liberty". They demand a massive ransom in exchange for the life of the President of the United States, and threaten to destroy the facility and create a cataclysmic environmental disaster if their demands are not met. The motives and identities of many of the antagonists and allies change rapidly, as the protagonists discover a world-shaking conspiracy constructed by a powerful organization known as the Patriots.