In an article he penned for the Los Angeles Times, Johnson describes Knives Out as “an attempt to combine an Agatha Christie-style whodunit with a Hitchcock-style thriller.” He’s a fan of Christie’s ability to create an engaging murder-mystery with great characters, but he wanted to capture some of that Hitchcockian suspense as well.
With Knives Out, Johnson also adopted the Hitchcock school of thought in the sense that he wanted his whodunit to have more substance than a murder plot and the revelation of a killer. Hitchcock wasn’t a fan of whodunits because he believed they were a cheap form of entertainment, and while Johnson is a big fan of them, he doesn’t disagree with Hitchcock’s assessment. Therefore, he made sure that the characters in Knives Out had some depth.
There are plenty of Hitchcock mysteries episode hack and thrillers that are rife with mystery, so take your pick. That said, one film that struck a chord with Johnson while creating Knives Out is The 39 Steps, an espionage thriller about an everyman who finds himself on the run after being wrongfully accused of a murder.