Revealing mistake: In the early part of the chase scene, when the person hanging the banner swings into the pane of glass, you can actually see it start to shatter before he touches it.
What's Up, Doc? (1972)
Plot summary
Directed by: Peter Bogdanovich
Starring: Barbra Streisand, Ryan O'Neal, Madeline Kahn, Kenneth Mars
When absent-minded Musicologist Professor Howard Bannister (Ryan O'Neal) arrives in San Francisco to try and win a research grant, the last thing he expects is to have his world turned upside down by Miss Judy Maxwell (Barbra Streisand), a girl who causes chaos wherever she goes. In the space of two days he gets mixed up with a millionnaire, jewel thieves, kidnappers, a spy and a government agent; accidentally sets his hotel room on fire, finds himself sitting on a grocery deliverer's bicycle inside a Chinese Dragon and ends up dressed as a Cantonese Mandarin in a car chase through the city in a stolen VW Beetle.
Lindsey
More mistakes in What's Up, Doc?
Eunice: I'm not looking for romance, Howard.
Howard: Oh?
Eunice: No, I'm looking for something more important than that, something stronger. As the years go by, romance fades and something else takes its place. Do you know what that is?
Howard: Senility?
Eunice: Trust.
Howard: That's what I meant.
Trivia: Much of Hugh Simon's dialogue was ad-libbed by Kenneth Mars.