According to
Johnny Depp on the Turner Classic Movies documentary on
Marlon Brando, In the scene where he and Brando are sitting at the table talking about the inconsistencies in DeMarco's (Depp) character, when DeMarco admits his father was from New York, Depp's lines were re written just before shooting the scene so he had no time to prepare and memorize the lines. So Marlon Brando talked to the Director and cinematographer to find out where the cameras angles were. He then worked out a way in which he cut up Depp's lines in the script and pasted them to the cup of coffee in his hand and then held the cup in his hand in such a way that the camera wouldn't pick up the pasted lines and Depp could read them.
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