The United Earth Sphere Alliance is a powerful military organization that has ruled over Earth and space colonies with an iron fist for several decades. When the colonies proclaimed their opposition to this, their leader was assassinated. Now, in the year After Colony 195, bitter colonial rebels have launched "Operation Meteor," sending five powerful mobile suits to Earth for vengeance. Built out of virtually indestructible material called Gundanium Alloy, these "Gundams" begin an assault against the Alliance and its sub organization OZ.