Comedy dealing with the adventures of Valère, a handsome and agreeable young man who has but one fault: he is hopelessly addicted to gambling. His refusal to mend his ways costs him the love of Angélique, who agrees instead to marry his uncle Dorante. The repentant Valère again wins her confidence, and Géronte, his father, agrees to pay the young man's debts. However, when Angélique gives Valère a jewelled portrait of herself, the temptation becomes too great. He pawns it, gambles, and wins but postpones redeeming the portrait. Word of the transaction reaches Angélique, and the portrait falls into the hands of Dorante.
Meanwhile, Valère has gambled again and has lost. Angélique confronts him with the portrait, ignores his lies and pleas, and agrees to marry Dorante.
Disinherited by his father, Valère is left penniless and friendless, but he still hopes to make his fortune by gambling.