In January 2018, 37-year-old Paul Mathieson was found fighting for his life on a street in Renfrew. The victim of a brutal assault, Paul succumbs to his horrific injuries and the skilled investigators of Police Scotland’s Major Investigations Team take up the case.
Despite the assault being caught on CCTV, the perpetrator is not identifiable and mysteriously disappears from the scene. Paul’s sister Amanda, a nurse at the hospital where Paul was taken, is enlisted to help appeal for information. For over five months some of the most skilled detectives in Scotland work tirelessly to try and identify the perpetrator. With a lack of any forensic evidence, vulnerable and unreliable witnesses the elements conspire against them.