They're in your laptop. They're watching your every click, every binge session, every guilt-ridden "Play next episode".
Yep, Netflix knows everything about your streaming habits - even down to the images you're most likely to click on when scrolling through their menus.
Global Manager of Creative Services Nick Nelson has taken to Netflix's blog to explain how the streaming giant fine tunes its thumbnail images to convince you to watch a show.
Turns out it's a lot more complicated than "make it look sexy". Here's what goes into Netflix's image choices.