Other mistake: After Carlson and Gloria have escaped their captors, they have to get to the Opera House ASAP to try to thwart the assassination of the pope and have to use 3 vehicles. I have frequently visited SF from the UK, and am familiar with the layout of the city. The route they take seems bizarre. They keep coming back on themselves, and at one point make a left onto California St behind a cable car. All they then needed to do was continue to the junction with Van Ness, take a left down to the Opera House near the intersection with Market St - yet still go off-route. I appreciate sat-nav hadn't yet been developed, so perhaps the film-makers were trying to evoke memories of Steve McQueen's car chase in Bullet.
Foul Play (1978)
1 other mistake - chronological order
Directed by: Colin Higgins
Starring: Chevy Chase, Goldie Hawn, Burgess Meredith, Rachel Roberts
Plot hole: When the albino kidnaps Gloria in the middle of the day, he is looking for the film obviously. So he would have checked her purse for it because that's where it most likely would be if she'd had it with her. But if he did check her purse, he would have seen all that "equipment" from Stella in there. But Gloria still has it when she comes to consciousness. What kidnapper would leave weapons in her reach? (00:48:35 - 00:50:05)
Tony Carlson: Want a joint? You know what they say, cops have the best dope.