There’s something terrifying about Slavov Zizek. He splutters and gesticulates like a football player in search of a penalty. He potters around Bodega Bay in a fishing boat fuming about Alfred Hitchcock. Why did the birds attack Tippi Hedren? The woman helming this Freudian inquest is Sophie Fiennes. Last month she squired her brother Ralph to the Bafta awards, kicking him in the leg to make him smile whenever the TV cameras were on his face. Tonight she is dating one of the wild men of film theory in a programme called Artshock: The Pervert’s Guide to Cinema.

Zizek is an unpredictable and unruly philosopher from Slovenia, Sophie one of the most subtle documentary makers I’ve met. The documentary is an extraordinary reassessment of cinema: a medley of 20 seminal moments in film which Zizek deconstructs with as much grace as King Kong. “He’s a hairy, sweaty, larger-than-life brain with an incredibly obscene sense of humour,” says Fiennes. “He plays with fiery ideas, and women find him very attractive.

“The idea was to invert the notion of film as a purely ethereal medium. So I placed Zizek in the films themselves. We rebuilt Dorothy’s apartment in Blue Velvet with footage of Kyle MacLachlan peeping from the closet. The reading is absolutely riveting. Zizek puts himself in Dennis Hopper’s skin. What is it about the scene that makes it so terrifying and compelling? For whose benefit exactly is this game being staged? “Zizek explores the answers from within. He sits on the loo which famously erupts with blood in Coppola’s conspiracy thriller The Conversation. I rebuilt the cellar in Psycho so Zizek could sit on the chair where the corpse of Norman Bates’s mother is discovered. And we hired a boat in Bodega Bay where Melanie is dive-bombed by a seagull in The Birds.”

It’s like an Open University film lecture from The Twilight Zone, philosophy as the new rock’n’roll. By applying rudimentary psychoanalysis key moments are interpreted in an entirely new light. “We are simply inventing a more stimulating way to look at cinema,” explains Fiennes.

She is far more intrigued by how people express themselves than by what they have to say. When she left school at 16 she had an inkling that she would never conform. She discovered the joys of documentary in her twenties via the punk ballerina Michael Clark, and Dogme maverick Lars von Trier. Her best films eschew narrative and are cut to perfection.

Because I Sing charts the strangest cacophony of voices yet assembled under one roof. The two-day concert at the Roundhouse in 2001 featured 16 choirs with nothing in common apart from an unnerving belief in the power of their own tonsils. Her next film, Hoover Street Revival (2002), was a magical document about neon faith in South Central LA.

“The Pervert’s Guide is a film I made out of frustration,” she says. As I write she is putting the finishing touches to two further episodes. I think we can safely assume she is hardly struggling.

Artshock: The Pervert’s Guide to Cinema, Channel 4

tonight (11.05pm)

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