The counterfeiting montage looks authentic because Friedkin consulted actual counterfeiters who had done time. The "consultant" actually did the scenes that do not show actor Willem Dafoe on camera to give this sequence more authenticity even though the actor learned how to print money. Over one million dollars of counterfeit money was produced but with three deliberate errors so that it could not be used outside the film. The filmmakers burned most of the fake money but some leaked out, was used, and linked back to the production. The son of one of the crew members tried to use some of the prop money to buy candy at a local store and was caught. Three FBI agents from Washington, D.C. interviewed 12-15 crew members including Friedkin who screened the workprint for them. He offered to show the film to the Secretary of the Treasury and take out anything that was a danger to national security. That was the last he heard from the government.