Arsène Baudu and Hyacinthe, a pair of small-time crooks, fall prey to Alexandre Larsan-Bellac, who involves them (against their will) in high-profile swindling, but their success is quite limited. For starters they are deceived by Mrs. Paterson, a charming widow. Later on, Ribeiro, a Portuguese contractor and former victim of the two crooks, traces them and forces them to work on one of his building sites for damages. Just then, Larsan-Bellac resurfaces with plans to lure Ribeiro once again.