Genoa, 1943. Grimaldi is a swindler, pretending to be a colonel in the Italian army to get money from the family of people put into jail by the Nazis. Once caught, the Gestapo makes a deal with him : he will stay alive if he impersonates the General Della Rovere, a leader of the Resistance who has just been shot by the Nazis, to be put into a political jail where he is supposed to identify another Resistance leader.