Waiting for Guffman
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During the overture, the trumpet player also plays the timpani. Although there is only one drum, we hear two distinct notes which would be impossible.
During the last scene in the play, a tuba can clearly be heard playing, but there is no tuba in the orchestra.
When the Stage Manager says, "We're at fifteen," her mouth does not move with the words.
The placement of the show posters on Corky's wall continually changes
In the Chinese dinner scene, the plate of beef to the left of Sheila appears and disappears.
In the Chinese dinner scene, Sheila's wine glass contains different amounts throughout the meal. At one point it's half full and then it's suddenly full.
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