Lelouch Lamperouge is a Britannian student living in Area 11, the land that was once known as the country of Japan. In 2010, the small island nation was invaded and stripped of its identity by the powerful Holy Britannian Empire.

After witnessing the crash of a military transport plane, Lelouch wanders into the midst of a restricted area in order to investigate the wreckage. His journey is cut short when patrolling Britannian soldiers threaten to execute him for trespassing. Fortunately, he is saved by the sole survivor of the crash: a mysterious woman named C.C. who he found confined in the plane's cargo. She grants Lelouch the power of Geass, a supernatural ability that demands the absolute obedience of those it is used upon, making his commands undefiable.

Now armed with devastating power, Lelouch assumes the persona of the revolutionary figure Zero, vowing to obliterate the accursed Britannian Empire and those who once wronged him many years ago.