Rush says when he got to the location he saw it was full of glass walls. "We had to suit what was happening inside with what was happening outside, and it opened up enormous opportunities", he said. "Also, I'd never shot a riot before with tear gas and policemen beating up people. When I suddenly had the equipment to do that, with the tear gas and the paddy wagons and the helicopters, it became a different version of the movie than I had originally pictured in my head as I had written it."