Every year thousands of offenders are convicted of sexual offences and subjected to a monitoring regime designed to minimise their risk to the public. But critics claim the system for managing offenders in England and Wales is flawed and allows offenders to slip through the net and flee abroad. File on 4 has discovered there are 559 sex offenders who are currently missing. One of them is Daniel Erickson-Hull – a self-styled pastor who was convicted of downloading hundreds of indecent images of children. On his release from prison he was subject to an order banning him from having unsupervised contact with children, unsupervised use of the internet and from travelling abroad without informing the authorities. But he ignored the restrictions and fled abroad. File on 4 tracks Erickson-Hull down to Bulgaria where he’s immersed himself in a Roma community and posted videos of himself with dozens of children online. File on 4 asks whether the laws designed to keep the public safe from convicted sex offenders are fit for purpose.

Reporter: Paul Kenyon