Every four days in the UK, a woman is killed by her partner or ex-partner - and in the past year, domestic abuse has become an epidemic.

For thirty years, Jane Monckton Smith has been fighting to change this. A former police officer and internationally renowned professor of public protection, she has developed her ground-breaking research into an eight-stage homicide timeline, laying out identifiable stages in which coercive relationships can escalate to violence and murder.

Drawing on disciplines including psychology, sociology and law, Monckton Smith talks to victims, their families and killers to piece together the hows and whys of abuse - while shining a searching light onto the society and media that allow it to thrive.