Sötétség, fogd meg a kezem

Blurb

From the back of the paperback:
When Detectives Patrick Kenzie and Angela Gennaro agree to protect the son of a prominent psychiatrist they soon find bodies are piling up around them. What's more, all the clues point to an unlikely suspect - a serial killer who has been in prison for twenty years, so he can't be killing again, can he?