Imagine: a paedophile grooming a twelve-year old girl, then going to have sex with her.

But it's a trap, and instead, he's confronted by Billy, a twenty-five year old cage-fighter who's been to prison three times and was abused in childhood.

Join Billy, his pregnant girlfriend and their fellow hunters, as they come to terms with their own abuse by posing online as children. Discover a community taking matters into their own hands, snaring paedophiles from all walks of life, from so-called family men and loners, to procurers working for rich and powerful paedophile rings.

Richard W Hardwick, acclaimed writer of The Truth About Prison, spent a year with the most notorious and successful paedophile hunting gang in Britain. This is what he found ...