Sep 28: The Truman Show (1998) dir. Peter Weir

Some films are set in an alternate reality. 

There are a few recent films which play with that trope of the Stepford Wives and other films, including a current film called 'Don't worry Darling' featuring Harry Styles which has had plenty of press coverage.

Spoiler Alert.

The Truman Show takes this to extremes in that the whole world which the lead character is fake: a simulacra.

If you haven't seen the movie, the trailer is a bit of a spoiler.