When body parts are found on the banks of the River Thames in Deptford, DI Anjelica Henley is tasked with finding the killer. Eerie echoes of previous crimes lead Henley to question Peter Olivier, aka The Jigsaw Killer, who is currently serving a life sentence for a series of horrific murders. When a severed head is delivered to Henley’s home, she realises that the copycat is taking a personal interest in her and that the victims have not been chosen at random.