78/52

78/52 (2017) is a documentary you can watch online on iFILM, directed by Alexandre O. Philippe and devoted entirely to a single piece of film: the shower murder in Alfred Hitchcock's Psycho. The title spells out the math — 78 camera setups and 52 cuts packed into roughly 45 seconds of screen time.

Filmmakers, editors and critics break the sequence down frame by frame to show how Hitchcock built a killing he never actually shows: the knife never once touches the body, yet audiences swear it does. Guillermo del Toro, Eli Roth, Karyn Kusama and editor Walter Murch dig into the cutting, the shriek of Bernard Herrmann's violins, and the sound of a blade stabbed into a melon. Jamie Lee Curtis talks about her mother, Janet Leigh, whose heroine dies forty minutes in — an unthinkable move for a movie in 1960. The whole thing is shot in black and white, fitting its subject.

This one is for viewers who love taking films apart bolt by bolt: not a recap of Psycho but a lesson in how editing wrings terror out of almost nothing. Stream 78/52 (2017) online on iFILM.