April. A second year high school student, Arato had a normal life he spent with his friends Ryo and Kengo. Until that night. On his way home from shopping, Arato is attacked by a corrupted hIE, but a beautiful hIE named Lacia comes to his rescue.

Despite his awareness of analog hacking, Arato can't help himself from being drawn to Lacia. Amid all of this, Lacia is "kidnapped" right in front of Yuka. Arato is upset with the police and their unwillingness to treat this as anything but property theft, so he gets the help of Ryo and Kengo to investigate on their own.

Arato arrives at the industrial promotion center which is the target for the antibody network's terrorist attack. He heads up the stairs and sees the android politician Mikoto his father developed, which leaves him with feelings of uneasiness. Soon after, the terrorist unit led by Kouka as well as another Lacia-class hIE arrive on the scene. A big battle is about to break out!

Arato manages to rescue Kengo from the calamity at the industrial promotion center. However, even after returning to normal life, he finds himself consumed by the ever deepening mysteries. Meanwhile at the Memeframe Corporation, a factional dispute becomes escalated. Within the upheaval, the Lacia-class hIE Methode is about to make her move.

Arato and Lacia walk towards the heart of the Higgins storage facility in order to choose a future. The two act like one as they help and support each other. However, damaged from the intense battle, Lacia does not have much time left...