The Unknown Lover (1925)

Upon the death of her father, a research chemist, Elaine Kent marries Kenneth Billings, the charming, irresponsible young son of a wealthy family. Kenneth is immediately disinherited by his father and, using a dye formula developed by Elaine's father, goes into business for himself, becoming extremely successful and devoting himself to work at the expense of his health. When Kenneth appears to be on the verge of a nervous breakdown, Elaine deliberately sets out to ruin his business by changing the bid on an all-important contract; Kenneth's creditors then quickly foreclose. When he discovers that Elaine was responsible for his bankruptcy, Kenneth accuses her of being in league with Fred Wagner, one of her former suitors and his biggest rival in the dye business. Kenneth, who then disappears for a year, returns from a sea voyage in the best of health and asks Elaine to forgive him for neglecting her. She then discloses that, at the time she changed the bid, she secretly went into business with Fred. Kenneth and Elaine are reunited, and he makes plans to resume his business career in partnership with Fred.