Plot hole: In the scene where John alone retrieves the mail from the postman, Iris dashes outside. Less than 10 seconds afer she closes the door, a car is heard, off-camera, honking a horn. Wouldn't John have found Iris so soon after that noise is heard? She doesn't seem to have enough time to allow for a search for her.

Continuity: Early in the movie when there is a lunch scene, the host fills the wine glasses. In the next shot we see the glasses empty, but after that they're full once again.