Big (1988)

Continuity mistake: During the piano scene in the background, various other extras appear, disappear and reappear between shots. Most prominent is a boy in a shirt with red, green and yellow stripes holding the hand of a smaller boy in red. These two are behind Tom Hanks and Robert Loggia in the front scenes on the piano but beside them in the side shots, and then proceed to alternate positions between these two shots, as well as appearing, disappearing and changing positions for the duration of the scene.

Neil Jones