Continuity: When Keaton and Nicholson argue outside the restaurant and Keaton confesses she is in love with him, in certain closeups Keaton holds her head with both hands. When the camera cuts to Nicholson's face, you see her back and her arms are down. This happens twice during the scene.

Factual error: After Nicholson's heart attack Dr. Mercer informs him that an EKG has revealed a blocked artery to his heart; I do not believe an EKG is capable of this diagnosis.

Continuity: In the scene of the freeze, where Erica and Harry first meet, see Marin's hair on her forehead change several times during close-ups.

Deliberate "mistake": When Harry is seen stepping outside of his hotel the evening after he arrives in Paris, behind him is the familiar Eiffel Tower gloriously illuminated against the night sky. Frequent traveller to the City of Light and resident alike may instantly recognize this hotel as the Regina, where many a movie has been shot on location (and where the late Princess Di was videotaped leaving one fateful night). Situated right across the street from the Louvre Museum and the Garden of the Tuileries, the Eiffel Tower simply cannot be spotted at all from the viewpoint depicted in the movie, let alone with such close proximity, even though it can be glimpsed in all its beauty further down the other side of the Seine river from the hotel rooms. The image is only a digital add-in to perhaps enhance the fact that Harry is indeed in Paris.

Factual error: The audition scene for Erica's play would never take place in the theatre. Auditions and rehearsals are held in rehearsal halls, not the theatre. Yet they show the sets already built and installed, lighting and effects in place, and they reference the costumes being ready. This does not happen until the show is close to opening.