Frank Warren is a treasury agent assigned to put an end to the activities of a powerful mob crime boss. Frank works undercover, posing as a criminal to seek information, but is frustrated when all he finds are terrified witnesses and corrupt police officers.
Recently paroled from prison, legendary burglar "Doc" Riedenschneider, with funding from Alonzo Emmerich, a crooked lawyer, gathers a small group of veteran criminals together in the Midwest for a big jewel heist.