The Face at Your Window (1920)

Two factory owners, Hiram Maxwell and Nicholas Harding are almost polar opposites -- Maxwell pays careful attention to his employees needs, while Harding totally disregards them. Maxwell's son, Frank, is very much like his father, and he is engaged to Harding's daughter, Ethel, who, unfortunately, has some of her father's less appealing traits. Naturally, she's not thrilled when he goes to work amongst the laborers at her father's factory. One of the other workers is Ruth Kravo, and both Frank and Ivan Koyloff are attracted to her. One night when Frank calls on Ruth, Ivan jealously stabs him. The trouble this causes loses Ruth her job, but she goes to work as a secret service agent amongst her own people.