This low-budget thriller, boosted by Bela Lugosi, was one of the biggest successes for the poverty row Producers Releasing Corporation (PRC). After the war, the studio tried to recapture this success by producing an in-name-only sequel, Devil Bat's Daughter, and a virtual shot-by-shot remake, The Flying Serpent.
This was the first, and most successful, horror film from Producers Releasing Corporation (PRC) after it was formed from the failed Producers Distrubuting Corporation (PDC). Filming began October 28 1940.