The 100 Society is more than just a game; it's an obsession. At Clifton Academy, sixth-form student Grace Becker will stop at nothing to carry out the rules of the game with her friends: tagging 100 locations around the city. But then the group catches the attention of a menacing stalker – the Reaper – who seems intent on exposing their illegal game, and the once tight-knit group starts to unravel…