Martin Compston puts all sign of Line of Duty’s DS Steve Arnott behind him in this compelling three-part thriller.

He stars as serial killer Peter Manuel, who carried out a series of brutal murders in Scotland from 1956 to 1958. Douglas Henshall is on equally fine form as stoic detective William Muncie, who knew Manuel of old and was convinced of his guilt.

As he struggled to get evidence, Muncie was constantly taunted by the arrogant killer.

The opener sees Manuel showing his true colours when he attacks a traumatised young girl and then sucessfully defends himself in court. His murderous spree is just about to begin…

A disturbing but fascinating watch.