I dokumentaren søker Leech å forstå hva som foranlediget brorens forvandling fra en vanlig middelklassegutt til den radikale Salahuddin, som mener at Storbritannia bør regjeres av sharialover og at utro kvinner bør steines til døde, og som nekter å ta sin egen bror i hånden fordi han er «skitten vantro» som kommer til helvete:
I first found out that Richard, my step brother, had become an Islamist in a newspaper article. My initial reaction was one of disbelief – it had to be someone else, or a mistake…but it wasn’t. Rich was the newest recruit of a man dubbed by the media the most dangerous man in Britain, Anjem Choudary.
In some respects the decision to make a film, My Brother The Islamist, was an easy one; I was an aspiring filmmaker and before my eyes was an incredibly topical, fascinating and unique story that I felt a responsibility to tell. But on a personal level, it was much more difficult. It was one thing telling a story, but to be deeply involved with the very emotional core of that story… I knew it would be a fine balance between the role of filmmaker and the reality of being part of a family so profoundly affected.
Luckily, the family were supportive. None of us knew anything about these sinister jihadists who Rich now regarded as brothers, or what they believed in, or even what Rich was like, now he had changed his name to Salahuddin and was calling for Sharia law across the UK. I wanted to get to the bottom of things and although the situation was extremely sensitive and upsetting for the family, I think they understood that making a film was my way of doing this, and if what I discovered on my journey could go some way to lift the ominous dark clouds of the unknown, they would stand behind me.
Dokumentaren ble først sendt på BBC 4. april 2011.