"Jo, it's me. We've found another body."
A body is discovered on a canal towpath in the small Yorkshire town of Shipley. DCI Callum Ferguson calls on forensic psychologist Jo McCready to help investigate the mysterious crime.
The victim is the second to be found on the canal in as many weeks, and Jo believes a single killer is responsible. Then, when one of her troubled patients is found brutally murdered, a puzzling connection emerges: is the murderer taking inspiration from the most notorious serial killer in Britain's history?
As DCI Ferguson and Jo McCready race to find the killer, the investigation takes more twists and turns than Yorkshire's canals. And with more questions than answers, can they solve it before another body turns up?