Working in the New York area, Eliot Ness and his men are trying to trace an incoming shipment of narcotics. Some years before, mobster and nightclub owner Jack "Legs" Diamond spent time in Europe and he made a deal with a Greek crime family to buy $5 million worth of narcotics. Diamond is flamboyant and loves publicity but his partners, Lucky Luciano and Dutch Schultz, want him to lay low for a while and they send him off to his cabin in the Catskills.