Revealing mistake: There is a short section where a U.S. soldier hops a rugged looking stone wall in France. As he goes over the wall, it moves back and forth a bit as if made of styrofoam and wood.
Revealing mistake: Near the beginning, after the corporal has burned his finger and tells the other corporal that Lawrence is balmy, O'Toole begins to run up the stairs to meet with a general. After O'Toole is out of view of the camera, you can tell he has stopped running up the stairs by his shadow on the wall not moving, because he knows that the director is about to shout "cut".