 The film was shot in Spain during the regime of Gen.  Francisco Franco (I) (qv). While the scene with the crowd chanting  the Marxist theme was being filmed (at 3:00 in the morning), police  showed up at the set thinking that a real revolution was taking  place and insisted on staying until the scene was finished.  Apparently, people who lived near where filming was taking place had  awoken to the sound of revolutionary singing and had mistakenly  believed that Franco had been overthrown.