Early 21st century. An incident of unprecedented magnitude sends shockwaves through the highest levels of the U.S. government: A prototype bipedal armored vehicle, Metal Gear, has been seized along with its nuclear payload by an armed group.
In a radical response to this crisis situation, the government calls in Solid Snake, the master saboteur who single-handedly brought down the fortress state of Outer Heaven seven years ago. The order given to him is to infiltrate into enemy's headquarters called "Galuade" and destroy Metal Gear.
Solid Snake by himself stands up against the impregnable armed fortress. But there awaits him is an unknown mercenary group who call themselves "Black Chamber."
Dark connections to the past, truths hidden behind the closed door are starting to be laid bare. So is the huge conspiracy surrounding Metal Gear...