In the Furnace Fire (1912)

John meets Mary and is invited to her home where he falls in love with her sister, Kate. They begin dating and John introduces her to his coworker Frank Johnson. Johnson lies, claiming John is a thief, causing Kate to leave John for Frank. John quits his job and leaves town, while Johnson marries Kate, but they are unhappy. Mary hires a detective who uncovers that Johnson is the real thief leading to his arrest while Mary informs John of his vindication. John returns, finds Kate denouncing Mary, and publicly rejects Kate by embracing Mary, revealing his true feelings for her.