Film-maker Rex Bloomstein, who pioneered a British prison television documentary, gains unprecedented access to the largest sex offender prison in Europe, HMP Whatton in the UK. Since the revelations surrounding high profile figures in the UK entertainment industry, there are more sex offenders in English and Welsh prisons than ever before, around 11,600 out of a total population of 86,000. Bloomstein explores the methods used to get prisoners to confront their offending behaviour and to prepare them to go back out into the world.