After a profoundly disturbing vision leads Rei to sacrifice herself in combat against the penultimate Angel, Armisael, Kaworu takes the opportunity to try to get closer to his own target. But Shinji's anger and confusion at Kaworu's advances develop into even darker feelings when events rapidly force him to come to grips with the secret behind the origin of Rei--a secret kept by the cold, brilliant mind of NERV's soul-sold genius, Dr. Ritsuko Akagi.