YouTube

Gang Busters is a 1942 Universal movie serial based on the radio series Gang Busters. The city is terrorized by a crime wave masterminded by the elusive, soft-spoken Professor Mortis (Ralph Morgan) from his base in a forgotten cavern beneath the rails of the city's subway line. He declares over the radio that The League of Murdered Men will exact revenge upon the city unless all the city officials, especially the mayor and Chief of Police, are turned out of office. Mortis's gang members were officially pronounced dead in prison after having supposedly committed suicide (in reality taking a drug that suspended animation) but later revived by medical genius Mortis, who recruited them to do his bidding. (Wikipedia)