In 2062, Earth engages in a fierce struggle against Artemis, a rebellious AI born from a failed automation project. To turn the tide, a trio of elite human fighters, dubbed the defenders of mankind, is mobilized. Empress, the sole surviving guardian, awakens in a deserted research facility with only fleeting memories of 'Lighthouse No. 8.' As she delves into her past, she unearths a looming danger posed by Artemis, realizing that she alone holds the key to preventing global devastation.