Men of Chance (1931)

Hoping to get even with gambler/bookie Johnny Silk, racetrack owners and partners Dorval and Farley convince down-and-out Martha Preston to pose as a rich, single French countess, whom Silk falls in love with and asks to marry. After the marriage Martha, who has genuinely fallen in love with Silk, innocently feeds his inside betting information to Dorval, causing Silk to lose a fortune. When she realizes what she's done, she confesses all to her husband, who becomes enraged and orders her out of his life. Faced with poverty, she teams up once again with Dorval as he asks her to betray Silk one last time.