When
Christopher Walken works with guns in film, he checks them himself before each scene for safety reasons and his own personal ease. During the scene when 'Sean Penn' sticks a gun in Walken's face, Walken checked the gun before the scene started. Before the director had the chance to say "Action", Penn ran off camera and shouted, "Give me the other gun!" He immediately returned to Walken and started the scene. This is the cut that made it into the movie, and Walken was really terrified.
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