In the Scre4m (or Scream 4) opening scene,
We see two girls get killed by two ghostfaces, but it turns out to be a movie scene from Stab 6 which is being watched by two girls. Then one of them kills the other. It turns out to be a Stab 7 movie scene, which is also being watched by two girls, and they're also killed by a ghostface, but that's the real scene of Scre4m film.
So the above scene shows a film within a film within a film. If I am not wrong then this kind of scene is not new and I have seen it before. So I want to know which film or TV series is the first to show this kind of scene?