Factual error: Shirley MacLaine and Jack Nicholson both live in River Oaks (very ritzy neighborhood in Houston) and are traveling to Brennans restaurant in downtown Houston maybe 5-10 miles away - but they go by way of Galveston which is about 45 miles south of Houston - which needless to say is way way out of the way... (00:50:40)
Continuity mistake: When Mary Carson is touching Father Ralph when he is shirtless her hands keep changing position between shots.
Factual error: Part of the movie takes place in Vienna, Austria. Although the number plates of the cars are like those in Austria at that time, neither the road markings nor the street car which can be seen when both Steve Martin and Kathleen Turner are "climbing" outside their hotel look like those in Vienna.Christoph Galuschka
Other mistake: In the scene where Jesse enters Monica's apartment, he consults her calendar to see in which class she is in school that day. There's nothing unusual about this until you look closely at the calendar and see that time time is early/mid August. Did her school's academic year run differently from other schools' years, or was she taking summer classes? The latter doesn't seem likely.