Arrived in Naples to work in the Doumenec family's factories, engineer Stefano Mascardi meets Rita, wife of Junio ​​Doumenec, eldest son of the industrialist Alfredo Doumenec, founder of the factory of the same name. A liking is born between the two but, soon, Stefano learns that Rita is involved in shady deals. The woman is in fact the lover of an unscrupulous man, Mr. Detoledo and, in agreement with him, has recently stolen an important industrial formula from Doumenec. When Mr. Detoledo is fo...