The Devil's Pipeline (1940)
A secretary sends a coded plea for help in her monthly report; two detectives investigate and find out that men are jailed on phony charges, forced to work in oil fields and then murdered if they try to escape.
A secretary sends a coded plea for help in her monthly report; two detectives investigate and find out that men are jailed on phony charges, forced to work in oil fields and then murdered if they try to escape.