In the future, the Galactic Federation and the pirates of planet Zebes are at war. Pirates have stolen an unknown life-form, recently discovered on the planet SR388. The life-form, designated “Metroid”, is in a state of suspended animation and, according to analysis, was the cause of the complete destruction of SR388. If the Metroid ever got loose, the alien could destroy countless other systems. It is up to the space bounty hunter Samus Aran to land on Zebes and find her way through the perilous terrains of Brinstar and Norfair, destroy the Pirates, as well as their alien enforcers, Ridley and Kraid, and rid the planet of the alien life form before the pirates complete their plans of world destruction.