Rhyme's cousin has been arrested for murder. The evidence shows he did it, but Rhyme agrees to check things out. It turns out that the cousin along with other people have been wrongly convicted because the true killer knows every single detail about the victims he kills and the men he sets up. Allowing him to get close to his victims and escape, then he sets up others to fall for his crimes, planting incontrovertible evidence. Rhyme, Sachs and the rest of the team find out who at an ominous data mining company is accessing the information and then the hunt is on ...