Gun Packer (1938)

JACK RANDALL...SHOOTS IT OUT IN DESERTED MINE WITH STAGE COACH ROBBERS!

Jack has been called in to investigate stage robberies where the stolen gold bullion mysteriously disappears, He finds the Professor, an elderly ex-con, and convincing him they used to work together, gets the Professor to get him in to the gang. Now posing as an outlaw, he learns what the Professor does with the bullion, but he is in trouble when his true identity is revealed.