Danger Lights (1930)

Head railroad man Dan is as ugly as he is honorable. When he spots a drifter who'd hopped a freight held up by a landslide, Dan offers the man a job; then he finds the man was a railroader, too, and takes him under his wing. Engaged to Mary, Dan doesn't notice the growing attraction between his protégé and his intended, but focuses instead on running the railroad.