Le piège de l'amour 103 years old

Maud married the banker Dumont mainly out of interest. As her husband accumulates mistresses, Maud writes to her favorite author, Jean d'Agrève, who is actually a charming old lady who think it best to give the letter to her son. The latter pretends he is the author in order to meet Maud. They become friends. But Dumont is assassinated and the young man is somehow accused of the murder.