Scenes set in Sir Alfred Hitchcock's Paramount Pictures suite of offices were filmed in Hitchcock's actual office on that studio's lot.
Dame Helen Mirren, who plays Hitchcock's wife Alma Reville, had also met the real Sir Alfred Hitchcock when he approached her for a part as a murder victim in his penultimate movie, Frenzy (1972). Mirren turned down the role, a decision she later regretted.
Sir Alfred Hitchcock biographer Patrick McGilligan noted several fictions created by the movie for artistic reasons. These included that in real life: Sir Alfred never re-mortgaged his house to help finance Psycho (1960)'s production. His wife Alma Reville never directed any scenes in the movie. His marriage was nowhere nearly as tumultuous as depicted. He never got involved during the production of the shower scene, and certainly never scared Janet Leigh.
Sir Anthony Hopkins met Sir Alfred Hitchcock when he was younger. Hopkins was accompanied by his agent, who introduced him to Sir Alfred in a restaurant.
Sir Anthony Hopkins wore a fat suit and latex make-up to play Sir Alfred Hitchcock, as he had recently completed a weight loss regimen.