Dennis Nilsen is one of Britain’s biggest serial killers of the 21st century, he has openly admitted to murdering fifteen young men at his homes in London. Was was it that drove an apparent respectable civil servant to go on a four year killing spree? Why did he confess all to police and who were those who escaped his murderous attacks?

In this episode of Real Crime these questions are asked as we discover more and more about the life of Nilsen. Through a number of interviews with police officers involved in his cases and those who survived his attacks we come to see who the real Dennis Nilsen was and what possessed him to commit such horrific acts.