This documentary about the shower scene in Alfred Hitchcock’s Psycho begins with an Edgar Allan Poe quote (already a bad sign). “The death of a beautiful woman is, unquestionably, the most poetical topic in the world,” it begins, desperate to locate lyricism in the Master of Suspense’s enduring fascination with dead blondes. But the film simplistically explains “the female body under assault” in the horror genre as a backlash to a changing postwar world, not daring to question Hitch’s personal brand of misogyny. More pretension abounds – like Psycho, the film is shot in black and white, calling on a celebrity cast of talking heads that range from Elijah Wood to Eli Roth to vainly analyse the iconic scene. To witness the sequence broken down in forensic detail is to appreciate its economy of storytelling anew, and to see its influence on subsequent popular culture, but to do so for 90 minutes might stretch even a superfan’s patience.