When instructed climb up the ladder to top of bridge, do so. Note: Enable the "Invincibility" or "Bullet shield mode" codes to make this easier. When you reach the top of the ladder, a Nazi will be directly in front of you. He will aim his gun at you and begin to shake. Do not shoot him or any other Nazis. Wait for a moment, and he will stand up, grab his helmet, and jump off the top of the bridge screaming.