In order to cope with chaos in society and in the classroom, the Japanese government has initiated the Battle Royale in which a classroom of 15-year-olds is chosen at random and shipped to a deserted island where they have three days to fight to the death. Only one student can survive, otherwise they all die. All of this is overseen by former teacher Kitano (Takeshi), and we follow this year's class centring on a boy and girl (Fujiwara and Maeda) who join forces with the winner of a previous battle (Yamamoto) to fend off all comers. And yes, it's a bloodbath.

The brutal violence is slightly undercut by a sense of satire and irony as the filmmakers nod at cultural issues (children out of control, first-world laziness). But nothing ever gets beneath the surface, leaving us to merely "enjoy" the film as an action thriller in which a group of fairly anonymous teens murder each other in increasingly gruesome and inventive ways. Lots of subplots help--a counter-attack by computer geeks, an enclave of gossipy girls holed up in a lighthouse, specific characters who launch particularly resourceful or relentless campaigns, even back stories told with colourful flashbacks.