Dark, gritty and always edge-of-your-seat: the number one best seller is back with a standout new heroine.

Unknown, alone and fearing for your life. As PC Lucy Clayburn is about to find out, going undercover is the most dangerous work there is. But on the trail of a prolific female serial killer, there's no other option - and these murders are as brutal as they come.

Lucy must step into the line of fire - a stranger in a criminal underworld that butchers anyone who crosses the line. And, unknown to Lucy, she's already treading it....

Always gripping. Always gruesome. Paul Finch will leave fans of Rachel Abbott and MJ Arlidge gasping for more.