Robert Armstrong, falsely accused of a murder committed thirty years ago in a western gambling hall, faces the alternative of imprisonment or paying blackmail. A letter from Tom Mason, formerly a miner, prepares him for a visit, at which time he must make his choice. Armstrong confides in his son, Dick, assuring him that the murder was committed by Mason, who used trickery to make it seem that he (Armstrong) was the culprit. Dick broods over the injustice to his father, and Armstrong cannot conceal his nervousness. The visitor comes and makes his demands. Armstrong grapples with him as the lights are turned off. Suddenly there is a shot, and when the lights are turned on again Mason is lying dead on the floor. Fearing the servants will enter, Dick drags the body through a window to the grounds outside, takes Mason's pistol out of his pocket, fires a shot into the body and places the weapon in the dead man's hand. Dick returns to the house and a policeman hurries to the scene. Dick ...