Mark Williams-Thomas is a multi award-winning investigative reporter. After a 12-year career with Surrey Police, he became an advisor for television crime dramas, and got his first on-screen presenting job while organising a sting on a German paedophile in 2008 for ITV’s Tonight programme. He has since reported on a number of major investigations, including the murder of Tia Sharp and the disappearance of Madeleine McCann. In this in-depth interview, he discusses his involvement with the Savile investigation – and how the existence of celebrity “untouchables” means there may be more to come.