In Louis Theroux: Surviving America's Most Hated Family, the filmmaker will re-vist the family at the centre of the Westboro Baptist Church 13 years after his first encounter with them, and explore the changes they have gone through.
Theroux first encountered the group, which is known for its inflammatory homophobic hate speech, for his 2007 documentary The Most Hated Family In America. He visited again for a follow-up in 2011 in America's Most Hated Family In Crisis.
In the new programme, Theroux immerses himself into their world again to find out what happens when a hate group largely populated by one family loses its patriarch – church founder and figurehead Pastor Fred Phelps, known as Gramps, in 2014.
He meets Pastor Phelps's granddaughter Megan, who has defected from the church and is now one of its biggest critics. He also meets a Bradford-born man who admires Westboro's rhetoric, given his own struggle to fit in with modern day Britain.
“I am always interested in how people change over time – physically and in their outlook – and even more so when they are involved in lifestyles that are somehow wrong-headed or self-sabotaging," Theroux said in a statement.
“With our unique access to the inner workings of the Westboro Baptist Church over the last 13 years, we've been able to track the changes in an extreme religious group from the inside, and also from the perspective of its ex-members.
“We've been able to tell a story about indoctrination, where it comes from, how it is enforced, but also about de-radicalisation, and the way in which a handful of those who were formerly zealots have managed to break free and take a kinder, less hateful view of the world.”
He added: “Gramps' angry and bigoted outlook had been the bedrock of Westboro's practices and I was curious to see whether his death might have caused any kind of break up or re-evaluation within the church, especially since there had been rumours that Fred Phelps might have had some kind of change of heart at the end of his life.
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“It was exciting going back for thirds. For their own reasons – to do with spreading their twisted take on the gospels – Westboro let me back in. For my part, it was a chance to see the strange machinations of psychology, religion and social conditioning.”
Patrick Holland, controller of BBC Two, said the new documentary “could not be more timely and important”.
Additional reporting by Press Association
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