Nate (the Bad Boy), Cooper (The Baseball Hero), Addy (The Popular Girl) and Bronwyn (The Clever One) find themselves in a detention they don't deserve with Simon, the author of a school app which discloses people's darkest secrets. Then Simon has an allergic reaction and dies. Who did it? 
 I thought this was a great book; a real cut above the usual writing about teenage angst. All four of the central characters are so well written and the nature of the story means that their characters are revealed slowly and with so much care that you really feel you have got into their minds. 
 Other than the four main characters, there is a really excellent supporting cast; I particulalry liked Bronwyn's sister and Cooper's "Nonny", but even the minor characters do have a part to play in bringing the story together and are equally as well written as any of the main four. 
 Of course, it wasn't really hard to guess who did it and how but by that stage it wasn't really the point. This is a book about having to come of age quickly and finding out who your real friends are when you need them and it does that brilliantly. Definitely a recommended read.