The human race nearly ended in 2000 A.D., when a top-secret encounter between an Antarctic expedition and an entity code-named "The Angel" triggered a global catastrophe. Now, in 2015, the Angels have returned, and Shinji Ikari, a fourteen year-old child of the new Earth, is summoned to the super-technological city of Tokyo-3 by his long-estranged father Gendo, and forced without warning to pilot the monstrous biomechanical weapon called "Evangelion" to match the fearsome power of the Angels. Beaten unconscious in his first sortie, only to have the Eva defeat the Angel on its own, Shinji tries to recover from an encounter he neither understands or remembers, and he is still disregarded by the father from whom he desperately seeks approval. Moving in with his commanding officer, Capt. Katsuragi, Shinji sets out to try and re-start a "normal" life in school. Neon Genesis Ecangelion Vol. 2 contains a special bonus interview with Yoshiyuki Sadamoto himself!
This is volume two of the manga series. I can't tell you what happens because in all honesty I haven't read it. It features Rei on the cover, so maybe you learn more about her in this one.