Revealing mistake: Just after the scene where the doctor asks Columbo to switch off the light before leaving, the detective does so, but it can be seen that both light switches are down before he does this, and that they are still both in the down position after he "switches off" the light.
Revealing mistake: Towards the end of the film when the old guy (Ed Begley Sr) is shooting a rifle at Clint Eastwood, the thumb of his left hand is on the top of the barrel, preventing him from seeing the front sight.
Revealing mistake: During the bank hold-up at the beginning of the film, one of the pushes a man on the wall. It wobbles like cardboard.
Revealing mistake: When Bullitt is in the Coffee Contata restaurant, he called Delgetti at the grungy hotel. Bullitt didn't look at a note for the supposedly unfamiliar phone number, but it seems as if the number wouldn't take much to remember, either. The number Bullitt dials on the rotary phone sounds as if it is made up of only the digits 1, 2 and maybe a 3, to not slow down the sequence.
Revealing mistake: When we first see Oliver Reed, we see his shadow first on the wall at a ramp to the pub. As his shadow spreads its legs, we then see him spreading his legs a moment later. Shadow puppetry was used by the director to give the audience the impression that he is ominous and foreboding before we ever see the man himself. (00:54:10)