She is called the"First Child". ( First Qualifier)

Yui Ikari (Shinji's Mother) DNA was used to create Rei. This explains the similarity between Shinji and Rei. After Rei was genetically engineered (by the Human Instrumentality Project/Human Completion Project) her genetic background was erased from all records. (The Rei that is seen now is the only one (several have died) to have a soul, a requirement for all pilots.)

While attending the 7th grade, Rei was the chosen as the first female Evangelion pilot. 1 week before Shinji was scheduled to arrive at NERV, Rei was injured during a boot-up sequence. (It is presumed that the root of the accident was Rei's mind wasn't strong enough, at that time, to keep control of the Evangelion Unit 0.) Rei, now, completes her duties perfectly, her reasoning for being a pilot is "the bond she has with her EVA".

Rei is always quiet, and never emotional and somewhat of a loner at school. Shinji and Asuka, are her only Friends!

"Neon Genesis Evangelion" StoryLine

(Music Rei's Theme Song )

In 1999, humanity found some sort of entity in Antarctica. The facts were covered up, but the entity may have been the First Angel, or Adam, or God Itself (if in fact these are not all one and the same). It was probably the entity called Adam, supposedly the first human being and possibly the First Angel as well. A scientific research team, including Gendo Ikari and the scientist father of Katsuragi Misato, sought to use science to understand the entity and reproduce its power on behalf of the human race. Misato was present as a young child. The "Second Impact," a tremendous explosion, resulted from their research. (The "First Impact" had occurred in the distant past, and was probably the explosion which killed off the dinosaurs and paved the way for the ascendancy of homo sapiens.) The most likely cause for the explosion is that an Angel showed up and came into contact with the first entity, turning Antarctica into a hellish ocean of poison and killing over half the human race. Gendo had left for Japan the day before the Impact, carrying much of the data they had so far collected; Misato's father saved her by placing her in a protective floating escape pod.

In the aftermath of the Second Impact, an ultra-secret committee called Seele (a word meaning "Throne of the Soul") arranged for the creation of NERV, a United Nations agency dedicated to the Human Completion Project, to push the human race into the next stage of its evolution, possibly the attainment of Godhood itself. The true facts of the Impact were hidden from the survivors of humanity, who were told that the Second Impact had resulted from the collision of a comet.

NERV was headquartered in the GeoFront, a perfectly spherical cyst-like cavern discovered in the Earth under Japan. Over the GeoFront was constructed the fortress city of Tokyo-3; the skyscrapers of this city were designed to retract into the ground, becoming suspended from the roof of the GeoFront, making them all but invulnerable to attack from above. NERV's headquarters was called the Central Dogma, located at the bottom of the GeoFront's sphere.

Ikari Gendo was made Commander of NERV. Seele was apparently guided in its actions by predictions/prophecies that had been found in the Dead Sea Scrolls but had been suppressed from public knowledge. The Scrolls predicted the advent of "17" Angels that humanity would have to defeat in order to achieve Human Completion.

Gendo's wife, Ikari Yui, was a brilliant geneticist who gave birth to a son, Shinji Ikari, less than a year after the Second Impact. Yui was instrumental in the creation of the "Evangelions" and was in fact an early if not the first test pilot of them. Evangelions are huge artificial biological organisms engineered from tissue collected from an entity named "Adam." They apparently have some form of rudimentary mind but no soul or willpower of their own. These elements are provided by human pilots, who are inserted in mechanical "entry plugs" into the beasts. An Evangelion with a human pilot synchronized within can generate an AT Field, making it nigh-invulnerable. The Evangelions are clad in metal "armor" which looks protective but is really intended more as a method of restraining and controlling the creatures. An Evangelion requires a constant feed of electrical power to move; its internal batteries die out within five minutes of unaided use, immobilizing the creatures.

Ikari Yui was "erased from the world" as a result of her experiments. There is an extremely strong implication that, while attempting to synchronize with an Evangelion, she lost her "ego boundaries" and her body liquefied into an undefined, primordial organic soup (this same fate happens to her son Shinji in one episode, but his soul manages to resist the call of merging with his Evangelion and redefine himself as a human, apparently largely due to his personal connection with Misato.) Shinji, aged 4, was present at his mother's "erasure" but later suppressed the memory. There is an unconfirmed implication that Shinji may have somehow been instrumental in the accident, leading to Gendo's estrangement from him.

After Yui's death, Gendo, who was always an unlikable sort, withdrew and became almost inhumanly cold and aloof, though brilliant. He abandoned his son to a private tutor and ignored him for the next ten years. Gendo became "romantically" involved with Akagi Naoko, mother of Akagi Ritsuko. Naoko was the leading computer engineer with NERV; it seems Gendo was dispassionately interested in meaningless sex while the elder Dr. Akagi was hopelessly in love with him. Naoko introduced Ritsuko, then a college student, to Misato, who was of similar age.

Misato, who had been aphasic (withdrawn into her own head) for two years following the Impact, had become an extroverted motor mouth thereafter, almost as if to make up for the lost time (as Ritsuko's mother observed). Misato took up with a young man named Kaji Ryoji, with whom she cut a whole week of college classes to do nothing but make love. Ritsuko, by contrast, was quiet and shy, and avoided contact with boys. It is likely Ritsuko had a crush on Gendo and was jealous of her mother. Misato, Kaji and Ritsuko all become good friends and all later joined NERV in various capacities.

Akagi Naoko designed and built the supercomputer system called MAGI, which consisted of artificial organic brains supplemented by electronic circuitry. MAGI was a triple system composed of three separate processors named after the Eastern wise men from the New Testament: Balthasar, Melchior and Casper. The core programming of each processor was a separate replicated portion of the older Dr. Akagi's own personality: her own thinking was replicated as mother, scientist, and woman.

At some point, Gendo Ikari began taking care of a strange, quiet little girl he called Ayanami Rei, claiming she was an acquaintance's daughter whom he was acting as guardian for. Rei looked exactly like a child version of Ikari Yui except that Rei was a white-haired albino, where Yui had been dark-haired. One night, Rei wandered into Central Dogma (the NERV headquarters) when Akagi Naoko was there alone. Rei dispassionately called Akagi a hag. When Akagi said it was rude to say things like that, Rei responded that she was just repeating what Gendo called her, "a tiresome, useless hag." Akagi, stung and infuriated, and seeing Yui in Rei, strangled the child, saying that "You are worthless, because you are replaceable... just like me." She then jumped to her own death. The events were completely covered up even within NERV; almost nobody knew of Rei's strangulation or the reason for Dr. Akagi's suicide.

For some reason, it was determined that only certain children born after the Second Impact could pilot Evangelions, supposedly identified as such in a report by the "Marduk Institute," an institution which later in the series is revealed to be a nonexistent front for NERV itself. Why these children were the only possible pilots is never really explained in the series. Three children were identified at the outset to the general staff of NERV as being designated pilots by the Marduk Report: Ayami Rei (who was alive despite her apparent strangulation), Shinji Ikari (son of Gendo and Ikari Yui), and Asuka Langley (a Japanese-American who was raised in Germany by a German stepmother). Only Rei was on hand before the attack of the Third Angel.

In a testing accident in 2015, Rei's Evangelion went berserk and attacked the control booth holding the command staff. Ritsuko privately concluded that it was trying to kill her (which later-revealed events suggest was probably due to a subconscious hostility by Rei, or possibly the Evangelion itself, against Ritsuko for being Gendo's lover). Rei was ejected, being badly injured, and in a surprisingly intense display of concern, Gendo burned his hands severely in rescuing her from her ejected entry plug. Rei kept and apparently treasured Gendo's eyeglasses, which were broken in the rescue.

By 2015 Ritsuko had taken her mother's place as chief technical engineer for NERV (and, probably, as Gendo's lover); Misato had long since broken up with Kaji, and had become NERV's chief tactical officer. The predicted appearance of the Third Angel and the arrival of Ikari Shinji in Tokyo-3 ended the "back story" and started the events that were depicted throughout the television series.

Upon arriving in Tokyo-3 during the Third Angel's attack, Shinji glimpsed a figure identical to Rei, who was then unknown to him, standing in the street outside the train station. This figure was uninjured, though at this time the "actual" Rei was still suffering from serious damage from her earlier accident. Shinji was taken down to the GeoFront and was instrumental in defeating the Third Angel.

Throughout, the children are assaulted by all seventeen Angels, no two of which were remotely similar to each except for their unanimous ability to generate an "AT (Absolute Terror) Field," a defensive shield making each all but invulnerable to any conventional weapon. AT Fields could apparently only be breached by another AT Field (such as that generated by an Evangelion), incredibly powerful energy weapons, or the Lancea Longini ("Longinus' Lance"), a huge metal spear of unknown origin in NERV's possession.

When Kaji and Asuka join with the Tokyo-3 team, Kaji brings with him a suitcase containing an embryonic entity he identified as Adam, apparently the living remains of the entity that had been found in Antarctica. Adam was purportedly scavenged and frozen by NERV and used as a genetic donor from which the Evangelions were engineered.

Adam was apparently installed in the Terminal Dogma, a vault at the bottom of the underground NERV headquarters, and the most heavily guarded point on Earth. One is lead to believe that Adam was unfrozen and allowed to regenerate in this spot, quickly growing into a giant, leg less white humanoid with seven eyes, which NERV immobilized by crucifying in the Terminal Dogma. This is an unclear point; this giant may not have been Adam after all. At a certain point in Adam's development Ayanami Rei was ordered by Gendo to impale Adam through the breast with the Lancia Longini, which may have halted its further regeneration but which did not apparently kill it.

Asuka Langley, the Second Child of the fictitious Marduk Report, was a brash, egotistical and somewhat nasty adolescent. A child prodigy, at fourteen she had graduated from college and had mastered several languages. Her synchronization rate, the measure of a pilot's ability to coordinate an Evangelion, was the highest of the three initial Children. Unfortunately, Shinji appeared to have a greater natural aptitude and quickly closed the gap between them. Shinji eventually surpassed Asuka, who couldn't handle being second-best very well. The situation deteriorated when Rei saved Asuka's life, putting Asuka into third place in her own mind. Asuka went into an emotional tailspin, attempting to dominate her Evangelion instead of merge with it, and her synchronization rate--and mental state--became progressively worse.

Ritsuko developed and installed a "dummy plug" system of artificial pilots for the Evangelions. The specifics of the system were not originally revealed, but the dummy plugs were described as soulless thinking machines duplicating Ayanami Rei's signal to an Evangelion. However, unlike Rei, the dummy plugs had no soul, according to Ritsuko.

The Lancia Longini was removed from the breast of "Adam" by Rei in order to kill the Fifteenth Angel, which attacked from orbit outside of any other weapon's range. Rei's Evangelion hurled it, javelin-like, into orbit. The Lance destroyed the Angel but could not be retrieved from orbit. The Fifteenth Angel, which attacked by some sort of long-range telepathic assault that manifested as a brilliant golden light and a deafening, imaginary chorus of Handel's "Messiah," had destroyed the last vestiges of Asuka's ability to synchronize with her Evangelion. Asuka was removed as an Evangelion pilot and promptly suffered a massive nervous breakdown.

The Sixteenth Angel, which appeared as a giant circle made from a double helix (resembling a viral gene's DNA, and also resembling a halo), attacked Rei's Evangelion and integrated itself into the Evangelions biological parts. Rei was ordered to eject, but for what was apparently the first time in her life disobeyed an order, so that she could detonate her AT field and destroy the Angel. Her shattered entry plug was salvaged and its contents whisked away. Miraculously, Rei appeared again, heavily bandaged but alive, with gaps in her memories of events.

Misato, concerned over the growing number of inconsistencies in what her superiors were telling her, was prompted by Kaji (himself a spy for the Japanese government and for Seele to keep tabs on Gendo Ikari's actions) to question what was really going on. Kaji revealed the seven-eyed Adam to her; Misato later seduced him into telling her what he knew of what was going on. Kaji gave her a capsule containing a data chip inscribed with his knowledge, but its contents was never revealed to the audience.

Shortly thereafter, Seele instructed Kaji to abduct Gendo's Vice-Commander, Professor Fuyutsuki Kozo, for intensive questioning; Kaji later released him, at the cost of compromising his own position within NERV. Misato, who had been suspended from duty due to her involvement with Kaji, was given back her gun and security card. Maybe Misato shot Kaji, because he was doomed anyway and by living he endangered her own position and ability to influence events, just as he himself was compromised. Then again, maybe she was only crying about Kaji's getting himself killed by someone else. A good argument could be made either way. But then, if Misato didn't kill Kaji, who did?

Ritsuko, anticipating that Misato would try to force information from her, arranged for Shinji and Misato to be present when she entered a restricted area of the Central Dogma. Ritsuko was disillusioned with her lopsided relationship with Gendo and was having a severe emotional crisis. She showed Misato and Shinji a graveyard of Evangelion skeletons from failed experiments and told Shinji about how he had seen his mother die. Then she revealed one of the secrets about Rei: a huge tank full of dozens of identical Rei clones. These, it turned out, were the basis for the "dummy plug" system; each dummy plug contained a soulless clone. Apparently three of these clones had been successively released as the living "Ayanami Rei." Only one at a time could have a soul, however, at least judging from what Ritsuko had to say (this is supported by a surreal sequence immediately prior to the second Rei's self-destruction, in which she talked with a duplicate image of herself standing knee-deep in liquid--apparently, in retrospect, the third clone). The first Rei had been strangled by Naoko; the second sacrificed herself and the third had recently been activated.

Ritsuko stated that she hated Rei and turned off the life support for the clone-tank, killing all the remaining dummy-clones. Why? Probably Ritsuko, like her mother before her, knew she couldn't compete with Rei for Gendo's affection, and this was her revenge. Ritsuko said this wasn't murder because the clones were soulless inhuman machines. She may have been telling the truth. Only the third Rei survived of all the clones. Ritsuko was removed from duty and locked up by NERV.

The Seventeenth Angel appeared in the form of a white-haired boy named Kouro, physically resembling both Shinji and Rei, who was presented by Seele as a new Evangelion pilot. Shinji was befriended by Kouro, who shortly thereafter told Shinji that he loved him. Shinji, isolated and desperate for contact, warmed up to Kouro and apparently loved him back. Soon after, Kouro activated Asuka's Evangelion without even getting into it; generated the most powerful AT Field on record, and easily defeated all attempts to prevent him from reaching the Terminal Dogma, including an attack by the despondent Shinki.

Kouro stopped just short of making contact with the seven-eyed giant, however. He told Shinji that only one being could survive the annihilation, and although Kouru was himself immortal it need not be him. He called the giant Adam then corrected himself and referred to it as "Lilith." Kouro declared that he preferred the freedom of death over eternal life and said that Shinji was the one that "needs a future." He asked Shinji to kill him, and, Shinji complied.

The final two episodes of the series are hard to interpret. They represent the long-awaited Human Completion, but are presented in a very stylistic, and occasionally downright surrealistic, fashion. There is no entrance segue and little context to determine what is "really" happening. Essentially, the premise is this: all humans are incomplete; they have a gaping void in their souls which is the source of all frustration, anxiety, despair and loneliness. Humans try to fill this void with the presence of other humans; thus humans are incomplete as individuals. Furthermore, others are needed in order to define one's own existence; without others, the self loses all definition and becomes formless (which may have been what had happened to Ikari Shinji, and maybe Ikari Yui as well). Human Completion merged all humanity into some sort of self-sufficient gestalt overmind. Maybe.

The form of the Completion is made manifest by a linking series of vignettes and montages exploring the character and personalities of the four principal characters, Misato, Asuka, Rei, and Shinji, as they exist within each other's minds and their own memories. Although all four have very different personalities, they are all shown to be acting out of their need for contact with others, which the Completion apparently supplies. The series ends with the Completion of Shinji, who surmounts his self-loathing and neurotic need to believe others dislike him; the ending note has Shinji accepting himself and stating that he likes being himself. He is then congratulated by the other characters of his acquaintance, who exist within his mind.

What "objective" reality has, is left undetermined. Perhaps with the death of the final Angel there is no such thing anymore. In the course of the Completion there was displayed a brief alternate continuity sequence in which the Angels, NERV, and Evangelions did not exist; the sequence was presented as a decidedly lighthearted adolescent gender comedy. The significance of all this is up for interpretation.

Many plot threads seem to be left unresolved. At one point in the Completion, images are momentarily shown of Misato and Ritsuko, both dead, without any explanation given; however, Misato continues to appear, alive, in the Completion sequences. Gainax, the Japanese company that produced Neon Genesis Evangelion, went on to make two theatrically-released sequels as theatrical releases, Evangelion: Death and Rebirth and The End of Evangelion. What bearing they have on the above is unknown at this time.

Ayanami Rei 1 was born from science, with no real parents. She was the prduct of cloning sciences that ahd received a jump start after the Second Impact, where most of the human population was killed.

Ikari gendo is the closest thing to a parent she has ever known. Ikari treated her as his own child, because in many ways she was; he oversaw her creation, and molded her in the image of his own dead wife, Ikari Shinji's mother. She is half gendo, half his wife; she is not aware of any entity that is "herself".

Ayanami Rei died very shortly after she was born, caught in the jealous rage of Dr. Akagi, the original creator of the Magi super-computer system. Furious as Rei related various insults at Dr. Akagi, which she had overheard from Gendo Ikari, Akagi stranged Rei to death and jumped to her death at the bottom of the Nerv Testing Center.

Rei was reborn as Ayanami Rei 2, a shell with the memories of the First Ayanami Rei but lack of total understanding of the nature of her death. Her deep seated respect for Gendo remained; he was the only one she would ever fully open up to.

Rei was recreated solely to be pilot for Evangelion Unit 00, the second of the Evangelion models to be constructed. The first Evangelion had obliterated itself as Nerv scientists tried to fuse it with Angel technology.

Unit 00 was imbued with the essence of Dr. Akagi, and Nerv was unable to completely control this essence. During a synchronization exercise, Unit 00 went berzerk with Rei inside it as it tried desperately to break through it's supports and kill Gendo Ikari. As Evangelion finally shut down and collapsed, Gendo Ikari pried the burning Entry Plug open with his bare hands, leaving permanent marks on his palms.

Rei was badly injured, and was unable to pilot as the first Angel finally surfaced and attacked the Geofront. She was spared the responsibility of fighting because of the appearance of Ikari Shinji, the Second Children, pilot of Unit 01, and son to Gendo Ikari.

Rei 2 recovered, and began to fight along side Shinji and Asuka Langley, pilot of Eva Unit 02. During one battle, her Eva unit was damaged and had collapsed. Shinji, however, pried open the Entry Plug just as his father did, bursting into tears when he found that Rei was uninjured. It was one of the few times she would ever smile.

It was demonstrated that Rei and Shinji had some connection, perhaps even beyond that fo Gendo and Rei, although moreunderstated. This was Rei's innder nature, the essence of Shinji's mother, manifesting itself. Although Shinji was unaware of this, he may have subconciously suspected this; it was Rei he always saw in his visions where he confronted his inner fears.

Rei, in a final, last ditch attempt, destroyed herself to save Shinji from a dangerous Angel. Before she died, she said "I want to unite with Shinji-kun", "Unite" meaning to marry/have sexual intercourse with.

Ayanami's death remained unknown to the others, however. gendo simply created another Ayanami Rei, and placed her in the Nerv infirmary. When Shinji thanked her for saving him, and asked if she remembered, Rei replied "I don't know. I think I am the third."