In Genoa, the Commissioner Sironi has identified the leader of the ferocious racket that controls the port activities. But the law restrains his action.
Carlo Antonelli, an engineer from Genoa, gets mugged and decides to take justice into his own hands. At first the muggers seem to get the upper hand, but then he's helped by Tommy, a young robber who takes his side.
A police captain arranges the release of a criminally insane prisoner, who soon winds up dead. When the District Attorney takes on the case, he uncovers corruption in the department and vows to take down the man who's responsible.
Inspector Betti (Maurizio Merli) is transferred to Naples and immediately after his arrival receives a warm welcome from The Commandante (Barry Sullivan), the city's crime lord. Betti then goes on a personal mission against corruption and organized crime, and tries to force the syndicate out of town with any means necessary.
Napoli'de, "Düztaban" lakaplı iri komiser Rizzo, yirmi yıldır cinayet, şantaj, hırsızlık, fuhuş ve uyuşturucu ticaretine karşı mücadele etmektedir. Tek başına ve büyük yumruklarını kullanarak birçok gangstere zor günler yaşatmaktadır. Bir uyuşturucu çetesinin Napoli'de yeni bir operasyon üssü kurmayı planladığını öğrendiğinde, yeni amiri tarafından görevden uzaklaştırılır. Rizzo, patronunun yozlaşmış olduğunu düşünmektedir.