O'Brien is "Whispering" Smith, so named because he speaks softly but knows how to fend for himself. The son of a railroad president, Smith is determined to learn the business from the ground up, so he gets a job as a track walker for his dad's rail line. While going about his duties, he meets Nan Roberts (Irene Ware), who is about to sell her Colorado ranch. Smith finds out that there are valuable tungsten deposits on her land and makes certain she won't be cheated by the villains

Les aventures d'un héros de l'ouest Whispering Smith, chargé de démasquer les pilleurs de trains.