Metal Gear Solid 2: Sons of Liberty is a stealth game developed and published by Konami for the PlayStation 2 on November 13, 2001. It is the fourth Metal Gear game written and directed by Hideo Kojima, the seventh overall game in the series and is a direct sequel to the original Metal Gear Solid.

The story revolves around the Big Shell, a massive offshore clean-up facility seized by a group of terrorists who call themselves the 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. The motives and identities of many of the antagonists and allies change throughout the course of the game, as the protagonists discover a world-shaking conspiracy constructed by a powerful organization known as the Patriots.