It's the New York Department of Weights and Measures vs. a systematic effort to cheat the public by giving them less product than they pay for...organized by crooked city alderman Marty Cavanaugh, who put the last chief deputy inspector in the hospital. The new man, pugnacious Johnny Cave, steps on the toes of influential merchants and gets increasing pressure, both political and strong-arm, to desist. Will the luck (if not the pluck) of the Irish pull him through?