Death Dealing Flies

Fu Manchu has left behind thousands of deadly flies that can kill with just one bite. Gunshots suddenly go off, and someone gets shot! A radio operator is killed, and Fu Manchu gets his hands on Formula 654. Smith, Petrie, and Sterling think Fu Manchu is planning to run away from St. Claire de la Roche, so they try to escape too. But they discover they are stuck because thousands of deadly flies are all around them, and their stings will kill anyone they sting.