Neon Genesis Evangelion, commonly referred to as NGE, Eva, or Evangelion, is a commercially and critically successful, influential and popular Japanese anime and manga that began in 1995. The anime was created by Gainax, written and directed by Hideaki Anno and co-produced by TV Tokyo and Nihon Ad Systems (NAS). It is an apocalyptic mecha action series, and refers to Judeo-Christian symbols from the book of Genesis and Biblical apocrypha among others. Later episodes shift focus to psychoanalysis of the main characters, who display various emotional problems and mental illnesses; the nature of existence and reality are questioned in a way that lets Evangelion be characterized as "postmodern fantasy" Hideaki Anno, the director of the anime series, had suffered from clinical depression prior to creating the series, and the psychological aspects of the show are based on the director's own experiences with overcoming it.