Louis Theroux has said that the thing that shocks him the most after years of documentary filmmaking is casual sex and “sex that is paid for”.

The broadcaster, who has worked on documentaries covering a range of topics such as Scientology, paedophilia and children with gender dysphoria transition, has also said that his famously calm, collected demeanour viewers see on screen is at odds with how he acts at home.

Theroux told the Radio Times, in an interview with Dawn O’Porter: “As odd as it may sound, there are things that shock me.

Louis Theroux
Louis Theroux (Matt Crossick/PA)

“Like infidelity. I’m always trying to get my head around casual intimacy, casual sex. Or sex that is paid for.”

Speaking about his new series of documentary films, he said: “One of the episodes in this series is about illegal prostitution and pimping. That was quite shocking.

“But I hear from women who are selling their bodies and giving all the money to their pimp, then I discover they were abused as kids and associate love with abuse and suddenly it all makes a bit more sense.”

Along with the film about sex trafficking, Theroux’s new US-based trilogy of films also sees him visiting Huntington, West Virginia, to learn more about the huge impact heroin use has on the community, and one of the country’s most racially divided and impoverished cities – Milwaukee, Wisconsin.

Louis Theroux
Louis Theroux (BBC/PA)

His other notable works include 2016 feature-length effort My Scientology Movie, 2007’s The Most Hated Family In America and 2003 documentary Louis, Martin And Michael.

Comparing his personal life to his work life, the father-of-three said that at home “I suppose I am more emotional” and “a bit more impatient”.

He said: “I get angry when I pick up my family’s clothes from the floor.

“I shout ‘Stop it’ and ‘Shut up’. Normal family interaction.

“People tell me I’m good not to lose my temper, but I never feel inclined to on location. But at home I lose my temper quite a lot.

“I’d love to find the person who doesn’t.”

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