Ah, yeah.
The Truman Show.
That was one of the few of his movies I mostly enjoyed.
An entire city of actors, with the "star" unaware?
Probably not that difficult, with modern technology.
I mean, all the cameras outside wouldn't even have to be hidden ... just claim they are security cameras.
And cameras are small enough to be virtually undetectable inside, unless you are specifically looking for them.
Heck, we could turn the entire city into "stars" ... and have a REAL "Big Brother" show.
Wouldn't even matter if they were aware of being filmed, as they would never know if they were being shown to the audience.