The story revolves around the Big Shell, a massive offshore clean-up facility seized by a group of terrorists who call themselves the titular "Sons of Liberty". They demand an enormous 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.
An expanded edition, titled Metal Gear Solid 2: Substance, was released in 2002 for Xbox and Microsoft Windows in addition to the PlayStation 2. A remastered version of the game was later included in the Metal Gear Solid HD Collection for the PlayStation 3, PlayStation Vita, and Xbox 360.
