Four victims.

Killer caught.

Case closed...or is it? 

Christopher Masters, known as 'The Roommate Killer', strangled three women over a two-week period in a London house in November 2012. Holly Kemp, his fourth victim, was never found.

Until now.

Her remains have been unearthed in a field in Cambridgeshire, and DC Cat Kinsella and the major investigation team are called in, but immediately there are questions surrounding the manner of her death. And with Masters now dead, no one to answer them.

DCI Tessa Dyer, the lead on the 2012 case, lends the team a hand, as does DCI Steele's old boss and mentor, the now retired Detective Chief Superintendent Oliver Cairns.

With Masters dead, Cat and the team have to investigate every lead again.

But if you'd got away with murder, what would you do when the case is re-opened?