It was a comedy movie. As written in the title, there were two heroes: a cop and a robber. The story took place in Italy just after the World War II. In the beginning, the robber cheated a American tourist 30 dollars. Then the tourist asked help from the police. A fat cop caught the robber with great effort. However, the robber was quite foxy and successfully escaped when he went to the bathroom.
The fat cop got severely scolded for his fault. His senior told him that he would be fired unless he could catch the robber in thirty days. In order to keep his job, he began to search for the robber everywhere.
Fortunately, he found the address of the robber in the archives. But the fat cop did not meet the robber in his home as he left home many days ago. For collecting more information, he made friends with the robber's family members.
At the deadline, the fat cop finally met the robber as what was desired. One thing unexpected happened. After thirty days communication with the robber's family, the fat cop turned to be sympathetic with their living conditions.
In the end, the robber went to the police with the fat cop, who promised to take care of his family.