This has been bugging me for years, and I’m 90% sure I haven’t posted the ID request before. I saw this movie in the late 1990s or early 2000s, and it was not very old at the time, so let’s say the movie came out between 1990 and 2010.
I think it was a Hollywood neo-noir, but that’s a guess. It seems to have been about Hollywood or the movie industry in general. The scene I remember: an actor and actress are being treated badly on set, and they get so fed up that they flee together, getting into a car and driving randomly up into the Hollywood Hills (I think) to escape.
Then something happens that’s straight out of the movie The Truman Show. The couple in the car come to a roadblock, preventing their escape. They get out of the car and look behind the roadblock, or poke through it or something, and realize their entire world is a stage set. There’s nothing beyond the roadblock except warehouses and vacant lots and whatever, and in that moment they realize they’re not even real people; the lives they thought they’d been living were merely part of someone else’s screenplay.
Resigned to their fate, they turn the car around and drive back to the set-within-a-set, to pick up their sad existences.