As a criminologist, Professor David Wilson's job is to get inside the minds of murderers, rapists and paedophiles.
From the Suffolk Strangler to serial killer Dennis Nilsen, David has met and worked with some of the most notorious criminals in Britain. So today, as part of Crime Week, he's going to give us an expert insight into the inner-workings of the people behind some of the most high-profile crimes ever committed in the UK.