Fever of the bone - Val McDermid

You should have been a detective. If there's one thing the last year has proved, it's how good you are at finding things out. Not simple things. Hard things. Things that nobody is supposed to be able to find out. Things that are buried so deep nobody even thinks twice about them. The sort of things that turn people's lives inside out once they're exposed.'
Meet Tony Hill's most twisted adversary - a killer with a shopping list of victims, a killer unmoved by youth and innocence, a killer driven by the most perverted of desires. The murder and mutilation of teenager Jennifer Maidment is horrific enough on its own. But it's not long before Tony realises it's just the start of a brutal and ruthless campaign that's targeting an apparently unconnected group of young people. Struggling with the newly-awakened ghosts of his own past and desperate for distraction in his work, Tony battles to find the answers that will give him personal and professional satisfaction in his most testing investigation yet.