How Long to Watch “RahXephon”?

Ayato Kamina thinks that he is just another high-school student with his own small part to play in the world until the day he meets the eerily familiar Reika Mishima. In a moment of extreme danger, Reika rescues Ayato and takes him outside of Tokyo, where it can be seen that the entire city is locked inside of a giant sphere. She explains to Ayato that the city he came from is now called Tokyo Jupiter and has been under the control of a menacing "alien" race called the Mu for the last decade. Ayato soon learns that he is of different origins than his peers, thus enabling him to pilot a specialized mecha called a Rahxephon, the only hope that humanity has for surviving against the Mu. Rahxephon draws inspiration from series such as Neon Genesis Evangelion in both appearance and metaphysical subtext. It also touches on the questions that arise as a result of the difference in the passage of time between Tokyo Jupiter and the outside world. Where is Ayato's true place in the world? And is there a reason that Reika seems so familiar?.