 The officials from Universal Pictures only found out that  Marlene Dietrich (qv) was playing Tanya when they saw the rushes  for that days filming; she had filmed her part in one day as a  personal favor to Orson Welles (qv) and he had not told anyone  about it. She agreed to appear at minimum union wages, but when the  officals decided to give her onscreen credit, they had to pay her  more.