Season 4 - Episode Guide

Examining how Howell Donaldson III terrorised a neighbourhood in Tampa, Florida in 2017, killing four random strangers.

After Gordon Wardell makes an emotional appeal to find his wife's killers, police soon realise they must look closer to home.

Investigating the murder of Brian McKandie. Initially deemed accidental, the handyman's death was soon considered murder due to his severe injuries.

When police find the body of Monica Massaro in her home with 17 stab wounds, they're led to serial killer Adam Leroy Lane.

When Lanell Barsock is found dead, evidence points to her boyfriend before detectives focus their investigation on best friend Larene Austin.

Seventeen years after his wife died in a car accident, Malcolm Webster became the focus of Scotland's longest ever criminal trial.

Documentary studies of police investigations into some of the most incredible and inconceivable murder cases in criminal history.

When elite racer Anna Wilson was shot and killed, police launched a manhunt to Costa Rica in search of Kaitlin Armstrong.

Documentary studies of police investigations into some of the most incredible and inconceivable murder cases in criminal history.

How Douglas Ward savagely beat and murdered Niall Dorr in 2010 in Dundalk, Ireland.