In Zane Grey's "The Mysterious Rider," a man, previously known as Bent Wade (now going by Bill), arrives at the Belllounds Ranch, where he was once the owner. He's come to uncover a past wrong and seeks revenge, while keeping his identity hidden, especially from his adopted daughter, Columbine. The narrative follows Bill's efforts to expose the truth about his partner's murder and reclaim the ranch, all while navigating his complex relationship with Columbine and the presence of a rival, Jack Belllounds.