Neon Genesis Evangelion (新世紀エヴァンゲリオン Shin Seiki Evangerion) is a Japanese animated television series, begun in 1995, directed and written by Hideaki Anno, and produced by Gainax. It takes place in 2015, fifteen years after the catastrophic Second Impact, reportedly caused by a meteor strike, which wiped out half of Earth's population and tilted its axis. Just as humanity is finishing its recovery from this disaster, Tokyo-3 began suffering attacks by strange monsters referred to as Angels. Conventional weapons are useless against the Angels, and the only known defense against them are the biomechanical mecha created by the paramilitary organization NERV, the Evangelions (Evas).

Although the series starts as a regular mecha anime, the focus tends to shift from action to flashbacks and analyses of the primary characters, particularly the main character Shinji Ikari. The creator/director, Hideaki Anno, suffered from a long period of depression prior to creating Evangelion; much of the show is based on his own experiences in dealing with depression and in psychoanalytic theory he learned from his psychotherapy. As a result, characters in the anime display a variety of mood disorders and problems with emotional health, especially depression, trauma, and separation anxiety disorder.

The television series aired in Japan from 1995 to 1996, ran for 26 episodes, and was released on VHS and DVD in North America and the UK by ADV Films. The show premiered on Adult Swim on Thursday, October 20, 2005, although it had been previously debuted in the United States in 2000 on KTEH, a PBS station located in San Jose, California. The first two episodes were also shown once on Toonami, albeit in a highly edited form.

The unedited / DVD versions received a Parental Guidance certificate, though some episodes are considered to be stronger than the certificate might otherwise indicate because they deal with issues of violence, emotional trauma, or contain some mild sexual themes.

Evangelion consists of 26 television episodes which were first aired on TV Tokyo from October 4, 1995, to March 27, 1996, and was followed by two movies: Death and Rebirth and The End of Evangelion, each first screened in 1997. Death and Rebirth is essentially a highly condensed re-edit of the series (Death) plus the first half of The End of Evangelion (Rebirth), while The End of Evangelion is a fully developed extension to the end of episode 24, intended as an alternate presentation of the series ending. The two movies were subsequently re-edited and re-released as a single movie, Revival of Evangelion (1998). Two additional DVDs, subtitled Genesis Reborn and Resurrection, were released. They contain both the original and director's cut of the final six episodes of the series.

In 2000, a group of scientists conducted an expedition in Antarctica where a large being of light, deemed by them as the first Angel, Adam, was discovered. On September 13 an attempt was made to capture it which ended in apparent failure when it proceeded to self-destruct, creating what would be called the Second Impact. The true nature of the Second Impact was concealed from the general public, who was led to believe that the devastation was caused by a small meteorite, traveling close to the speed of light, impacting in Antarctica.

In the conflict with Angels, mankind is represented by the mysterious organizations NERV, GEHIRN (which started out as the investigation team for the Second Impact but became NERV later on), SEELE, and the Marduk Institute. NERV is, in theory, under the control of SEELE, but NERV has its own agenda, driven by its commander Gendou Ikari. NERV carries out two tasks: to defend the Earth from Angel attack with a small number of Evangelions (Evas), and the Human Instrumentality Project, which, according to Gendou, is the path to becoming one with God.

Eva Unit 02 crouching on the missile destroyer USS Ramage.

The Evas have the outward appearance of massive humanoid robots and can apparently be piloted only by children conceived after the Second Impact. Pilots are selected by the Marduk Institute, which is later discovered to be composed of about 108 ghost companies, (108 is the number of sins in Japanese Buddhism, and the number of beads on a typical Buddhist rosary/mala) but Gendou Ikari and Ritsuko Akagi are actually in charge of selecting pilots. It is frequently speculated that qualifying pilots must have lost a mother, whose soul is used as the soul of the Eva. (This has been debated due to the probability that Rei is a clone of Yui and therefore doesn't have a technical 'mother' but some fans believe that Yui's soul was split between Unit 00 and Unit 01 (further evidenced by the fact that both are deemed Prototype Eva while Unit 02, which if this assumption were correct would have a non-split soul, was the first "official" Eva Unit). This theory coincides with Rei and Shinji's ability to synchronize with each other's Evas.) The Evas also appear to behave under the influence of the soul inside it. One example is when Unit 01 goes "berserk," acts without control of its pilot or NERV and refuses to shut down (or in one instance, to start without Shinji). Unit 00 goes berserk and lashes out at the tormentors of Ritsuko Akagi's mother, apparently attempting to kill Rei. Though unit 02 does not ever go truly berserk, Asuka says in "The End of Evangelion" that she feels the presence of her mother protecting her in the Eva. The term "berserk" really only befits the actions of Unit 00; Unit 01's actions were focused, restrained, and beneficial to Nerv's missions.

Each Eva has its own designated pilot, due to the bond between the pilot's soul and the soul of the Eva; otherwise, any other person who tries to synchronize (simply put, to technically work as one mind) with the Eva is more likely to be refused. That is not to say that it is impossible to synchronize in such a situation, as is shown in an experiment in Episode 14, in which Rei and Shinji synchronize with each others' Evas. It is later apparent that the Evas are not really "robots" but rather living, biomechanical organisms, in contrary to the popular belief of the general public. While Ritsuko does mention at the beginning of the series that the Evas do have some biological components to them, the extent to which the Evas are biological is not immediately apparent; it is finally revealed, towards the end of the series, that Evas are essentially Angels (made from Adam, the first Angel, except unit 01 which is almost certainly made from Lilith, the second Angel) onto which mechanical components are incorporated during its creation — part of the reason being to restrain and control them.

The secret second task, the Human Instrumentality Project, intends to start an artificial evolution of mankind. Considering the religious implications of the term "evangelion," this event was said to bring about the salvation of mankind in the context of a newly created Earth and humanity's becoming one with God. SEELE is the main driving force behind this project, for reasons unknown, but they mention that humanity must evolve or it will die, thus the need for a forced evolution. This artificial evolution strives to merge all human souls into one by disposing the individuals of their AT-Fields that separate egos from each other. This causes their bodies to revert to LCL. When everyone comes to this state, they will no longer feel the pain or loneliness that would typically precipitate from interaction between humans; it is comparable, but not equal, to death.

The plot of The End of Evangelion and the plot of the series seem to diverge at the end of series episode 24. In the series, episodes 25 and 26 consist of abstract introspection by the characters, especially Shinji. The ending is left open to interpretation: clearly, Shinji eventually overcomes his issues with others and comes to accept being with them, but whether Instrumentality follows through or if it occurs at all are left unanswered, directly. The specifics of Instrumentality are not explored in the series, either. In End of Evangelion, Shinji is directly involved in the initiation of Instrumentality, but ultimately rejects it at the last moment. There is some debate as to whether The End of Evangelion is a complement to, or a replacement of the TV episodes 25 and 26. The highly stylized nature of these episodes leaves them very open to interpretation. Some fans believe that the final scene of episode 26 where all of the characters are shown telling Shinji, "Congratulations" is a sign that Shinji accepts the Instrumentality Project and therefore is at odds with End of Evangelion. Others believe that the characters are congratulating Shinji for finding his own identity, as his realization that he is an individual identity is the deciding factor in whether or not Instrumentality will occur (therefore, the characters are congratulating Shinji because his decision to remain an individual means that they can all remain individuals) - this interpretation is reconcilable with End of Evangelion. The line is sometimes considered to be a reference to the end of Space Runaway Ideon, in which case it ironically implies a Pyrrhic victory and death. Yet another group of fans sees the final two episodes as being a part of the introspective detours from the second half of End of Evangelion. It has also been pointed out that episodes 25 and 26 could be the psychological process that Shinji goes through at the point just before he merges with Lillith in "The End of Evangelion", thus rejecting Instrumentality and Lillith as he discovers his individualism.

- From Wikipedia