Louis Theroux: ‘I worry about not coming up to scratch’

He made a film on Joe Exotic a decade before Tiger King, lulls interviewees into personal revelations - and can rock a leather suit. So why is he so anxious?

There's no getting away from the fact that, even aged 50, I'm a slightly awkward person, a fearful person, worry-prone," says Louis Theroux, wriggling in his seat. The film-maker picks up and puts down a coffee without drinking. He wears all blue: navy sweater, stock denim, one of those indestructible plastic Casio watches on his wrist. I worry about what people think," Theroux continues, I worry about giving offence, being judged, not coming up to scratch, being thin-skinned."

We are in the corner of a photography studio in London, sheltering from rain on a Friday afternoon. The room has long emptied of people, but, even so, as Theroux chats, he snatches quick glances over his right shoulder, as if expecting to find somebody or something lurking there. Everyone has things that preoccupy them, right?" he says. I just tend to think, on a spectrum of people in general, I definitely skew, uh, anxious."