Frank Nelson's movie debut.
Banned in Austria, Switzerland, Cyprus, Finland, Trinidad and France. The ban in France was lifted after a year, and it opened to extremely negative reviews. Australian and British release versions were heavily censored.
Director Michael Curtiz was brought in to shoot some additional footage after the production wrapped. It is known that he shot at least the scene with the Black Legion executives.
The film that Betty and Ed go to see early in the film, 'All For Love' is completely made-up, as are all the posters for the other films outside the theater. Titles that are visible include 'Jail-Break,' 'Bengal Tiger,' 'Public Enemy's Wife' and 'Big Noise.'
The location used for the machine shop is actually the real Warner Brothers machine shop, which still exists and can be seen today on tours.
The movie was inspired by a real case involving the Black Legion in Michigan, where a WPA worker was killed.
Warners would produce a similar-themed film, Storm Warning in 1951 about a for-profit hate group similar to the Black Legion.
When Frank lights a cigarette outside the pharmacy after his wife and child leave, an advertisement for Pabst Beer is visible behind him, only the P and the T have clearly been covered with white-out.