A sweltering summer day on the Hobfield housing estate. New tenant Lisa Woodley is horrified when her cat comes home with a human foot in its mouth.

The foot belongs to 16-year-old Noah Crosby, whose decomposing remains are found in a rubbish-strewn alleyway. It’s not a robbery, as the kid has a gold watch, high-end trainers and a top-of-the-range mobile phone on him. Where did he get such expensive gear?

A letter X is carved into Noah’s flesh. Twenty years ago this was the hallmark of a serial killer who was never caught.

Is he back killing again?

Detectives Calladine and Bayliss reach a dead end. People are scared. No one will talk.

Then Calladine’s new girlfriend’s shop is targeted – and it’s clear she’s not telling him the whole truth about the attack. Just what is she hiding?

Can Calladine and Bayliss get answers before the murderer strikes again?