It is the autumn term and Greer MacDonald is struggling to settle into the sixth form at the exclusive St Aidan the Great boarding school, known to its privileged pupils as S.T.A.G.S.

To her surprise Greer receives a mysterious invitation with three words embossed upon on it: huntin' shootin' fishin' - an invitation to spend the half-term weekend at the country manor of Henry de Warlencourt, the most popular and wealthy boy at S.T.A.G.S. Greer joins the other chosen students at the ancient and sprawling Longcross Hall, and soon realises that they are at the mercy of their capricious host.

Over the next three days, as the three blood sports - hunting, shooting and fishing - become increasingly dark and twisted, Greer comes to the horrifying realisation that those being hunted are not wild game, but the very misfits Henry has brought with him from school...