After a fruitless nationwide search for an authentic 1930s police car, the car wrangler came across a "barn find" of a 1931 Ford Model A that had not been started for 15 years. The rapid 1-month restoration was completed just in time for the first day of shooting. Miraculously, the 85-year old car ran for 7-straight hours without stalling or overheating.
The location for the "dungeon under the speakeasy" was an ACTUAL speakeasy back in the 1920s. The secret room was hidden under the Star Hotel in Marcus Hook, PA - a port frequented by sailors back in the day. The original hidden stairways and plastered walls can be seen in the movie.