A series of brazen, violent and ritualistic murders have police baffled and the killer leaves few clues as to their motive or identity. Inspector Eric Ringer is desperate for Dr Jane Halifax to profile the killer but memories of their last case make Jane hesitate to take on the case. But there's something about the killer that intrigues Jane and as more bodies join the list of violent murders she is compelled to find answers. A psychopath is a psychopath any way you slice it and this is where Jane Halifax excels – but she must overcome her own apprehensions and get into the mind of this killer before he strikes again.

In this episode Gregory Dobbs chats to Roger Simpson about turning the highly successful TV series Halifax f.p. into a dark and twisted psychological thriller, how the passage of time has treated his characters after a twenty-three year interlude, and what you can do in a novel that you can't do on a TV screen.