Double Indemnity (1944)

Factual error: There's a scene when Barbara Stanwyck hides behind an open door to avoid beeing seen by Edward G.Robinson leaving Fred MacMurray`s apartment. To make this possible the apartment door opens outside into the corridor, which is an elegant solution for this situation in the movie. But in the real world no apartment door would open by swinging into the corridor because this would give a visitor standing there a punch on the nose when the resident opens the door.

Walter Neff: That was all there was to it.Nothing had slipped, nothing had been overlooked.There was nothing to give us away. And yet, Keyes, as I was walking down the street to the drugstore, suddenly, it came over me that everything would go wrong. It sounds crazy Keyes, but it's true, so help me, I couldn't hear my own footsteps. It was the walk of a dead man.

Trivia: Fred MacMurray wears his real-life wedding ring throughout the movie. His character in the movie is single.

Question: Why would Nino come to visit her every day when she knows she is being watched?