A class of ninth-grade students, plus two outsiders, are taken unwillingly to a small isolated island. Each is given a map, water and a randomly chosen weapon. They have to fight each other for three days until the last one remains; if not, they all die. Each is forced to wear a special collar which will explode when they break a rule. Friends and lovers and mere aquaintances then start their bloody battle with weapons from nothing to a head band to a sword to guns (the later being most common). The film include teenagers who murder with little conscience and remorse, those who are unable to fight and fall victims easily, and those who attempt to escape this doomed island.
Fukasaku Kenta adapted Battle Royale from the novel by Takami Koshun. The book and film bear some parallels to the story The Most Dangerous Game, as well as the William G. Golding novel "Lord of the Flies" and the Stephen King book "The Long Walk". Takami was an admirer of King, and named the students' home town and school "Shiroiwa," which translates to "Castle Rock," the name of a town frequently used by King as a setting for his stories. King, in turn, had borrowed the name from a location in Golding's novel.
Battle Royale was generally well received amongst critics who appreciated it as a satire of the Japanese education system and a metaphor for the perpetuation of violence from one generation to the next, but some educators and politicians objected to the violence perpetrated on screen by the 15 year-old students. Attempts by these politicans to have the film banned in Japan failed, however, and it was released with an R-15 rating to great box office success. A Special Version later released was more gory (CGI blood enhancement and addition, close-ups, and extra sound effects to emphasize the violent acts or deaths) than the original, contrary to the popular belief that it would be more "toned down" to suit the general public's taste.
The soundtrack, mainly composed by Masamichi Amano and performed by the Warsaw Philharmonic Orchestra, features several pieces of classical music, such as by Strauss. The end credit is accompanied by Dragon Ash's "Shizuka na Hibi no Kaidan Wo" (静かな日々の階段を Climb the Stairs of Quiet Days), which is absent from the soundtracks.
Kinji Fukasaku elected to direct a sequel, Battle Royale II: Requiem in 2003, but died of bone cancer on January 12, 2003, after shooting only one scene. His son Kenta, born 1973 in Japan, who wrote the screenplay for both films, completed the film in his stead.
In the sequel, survivors of previous Battle Royales, lead by Shuya Nanahara, have formed a terrorist group, Wild Seven, and the government creates a new Battle Royale game wherein the chosen class must storm Wild Seven's island stronghold and kill its leader.
The sequel's soundtrack has a lighter selection of class music, and more emphasis on original work by Amano.