It was sci-fi short story or novella that I read in Analog, Asimov's or SF&F in the past decade or so.
Set in a future extrapolation of our social-media, fan-centered world inside a future mega movie theater entertainment mall, where a late high school/ early college aged girl is with a group of friends and she really wants to see a certain movie and is consistently and conveniently redirected from seeing the one she is interested in. She ends up becoming intrigued by a boy at the theater acting strangely and becomes involved in the undercover "kid's" mission within the theater. The premise is that so many movies were being made, that a conspiracy formed where some movie companies started to advertise and market movies and merchandise for movies that they never actually filmed, and they were getting away with it.
