This is the long (long long) novel that is the basis of the more well-known film by the same name. A group of middle-schoolers presumably on a class trip by bus as fed sleeping gas and wake up in an unfamiliar classroom being told that they have been chosen for the project (and are among dozens of other classes in the same situation) and will be sent out onto an abandoned island with one weapon with the idea that the last surviving class member will be allowed to live. There are electronic collars around their necks that will explode if they remain too passive, stay in forbidden zones (the whole arena is made progressively smaller over time), or if they try to escape or fight the guards. It seems like every consideration has been accounted for.
From there we follow the 40 or so different classmates through their own individual and intersecting experiences with the battle royale.
Like the movie, this book has been cited as the clear influence for the Hunger Games and the comparison is apt not just because of the central conceit, but because of many of the different ways that the author gives us specific insight to the characters and how this experience colors them, and how this event is a kind of release valve on a repressive society.
Ultimately, while this book is interesting in concept, it’s actually kind of boring and trite in terms of its thematic goals. The characters often are hard to follow, the action is gruesome but plodding, and the social commentary is weak at best.