A body is discovered at an exclusive hotel, drawing DCI Sarah Allerton and her team into the perilous world of human trafficking where a life means zilch. The gangsters will do anything to protect their identities. No one is safe.

While probing the case, a cold shadow from Sarah’s past threatens to destroy her life. After seven long years, the Cambridge Serial Killer returns, determined to continue his spree of sadistic murders by threatening Sarah’s partner, the only one to escape his clutches.

While clues from the trafficking crimes stack up, Sarah is forced into a race to halt the serial killer’s reign of terror and protect all she holds dear.