Apple are so protective over their precious iPhones that they won't even let the bad guys use them in films, it turns out.

Speaking to Vanity Fair, director Rian Johnson let the secret slip while dissecting a scene from his latest film Knives Out. `I don't know if I should say this or not,` he said. `Apple, they let you use iPhones in movies, but, and this is very pivotal, if you're ever watching a mystery movie, bad guys cannot have iPhones on camera.`

Johnson actually explained that iPhones can even be a kind of spoiler. This next part is going to be a spoiler for Knives Out. I cannot stress enough how much we're about to give away the film for you. If you haven't seen Knives Out, close this window and then take a long hard look at yourself - it's an excellent film.

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Knives Out director Rian Johnson let slip an industry secret about Apple's strict rules prohibiting villains from using iPhones on camera.

A post shared by ign (@igndotcom) on Feb 26, 2020 at 4:31pm PST

While dissecting a scene between all of the Thrombey family members ahead of the reading of the late Harlan Thrombey's will, Johnson notes that Jamie Lee Curtis' character Linda Drysdale is seen holding an iPhone. This led him to let the rest of us in on the Hollywood secret.

It turns out that all of the suspects in the film can be seen with iPhones except Ransom Drysdale (Chris Evans), who is eventually revealed as the key villain.