The Apartment (1960)

Factual error: At the end of the scene where CC Baxter meets the doctor for the first time in the hall, Baxter is standing in the doorway of his apartment as the doctor enters his own apartment. From that view, you can see into Baxter's kitchen, which has a window - right where the apartment the doctor just entered is located. That could not be an outside wall.

Chip Bergquist

C.C. Baxter: The mirror... It's broken.
Fran Kubelik: Yes, I know. I like it that way. Makes me look the way I feel.

Trivia: To make the office appear larger than it was, the team used forced perspective - adult actors at the front, with child actors behind them, and tiny desks with wire-operated dolls at the back.