The Diclonius are a species of evolved humans with two cat-ear like horns and vectors, transparent telekinetically controlled arms that have the power to manipulate and cut objects within their reach. Diclonius are being held in a facility off the coast of Kamakura in Kanagawa, south of the city of Yokohama, by the scientist Kurama. The first of the Diclonius race, a teenage girl named by the staff as "Lucy," escapes, using her vectors to deflect gunfire and effortlessly kill security guards. As she makes her way out of the facility, a sniper shoots her, breaking her metal helmet and causing her to fall into the sea. The next morning, Kohta is moving to Kamakura to study in a university where he is reunited with his cousin Yuka. He encounters Lucy on a beach in the area, naked with her head bleeding from the bullet wound and only capable of saying the word "Nyu." Kohta and Yuka decide to take her with them, naming her "Nyu" as a result.