In an interview with Vanity Fair today, Rian Johnson, who directed the popular movie "Knives Out," shared an interesting tidbit about iPhone product placement deals for films. Apple, he says, allows iPhones to be used in movies, but bad guys aren't allowed to have iPhones on camera.

The relevant passage starts at 2:50 into the video

Also another funny thing, I don't know if I should say this or not... Not cause it's like lascivious or something, but because it's going to screw me on the next mystery movie that I write, but forget it, I'll say it. It's very interesting. 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. So oh nooooooo, every single filmmaker that has a bad guy in their movie that's supposed to be a secret wants to murder me right now.

Apple is known for having strict rules about how devices are used, portrayed, and photographed. As part of its guidelines for using Apple trademarks and copyrights, for example, Apple says that Apple products should only be shown "in the best light, in a manner or context that reflects favorably on the Apple products and on Apple Inc."

As noted by our forum members, people have in the past pointed out that it's the good guys that use Apple products in TV shows in movies. When "24" was on the air, Wired wrote about a fan theory that the good guys use Macs while the bad guys use PCs, which turned out to be accurate.

Given this tidbit from Johnson, who is a well-respected director, many people may be watching movies with a much keener eye on the devices that actors and actresses are using to suss out hidden details.