A brutal game devised by three intelligent but bored teenagers escalates into murder. Led by the charismatic and cunning Laurence, the trio of `brothers` meets once a year to carry out untraceable, motiveless murders – for fun. Until, years later, they must murder in order to protect one of their own, leaving themselves vulnerable to discovery. The killing is investigated by Detective Inspector Paul Snow, a complex man with a secret of his own which links him to the murder. As Snow grows closer to unmasking the killers, his professional life begins to unravel in a terrifying fashion.