In Golden Spike, the final book in The Iron Horse Chronicles trilogy, Will Braddock is working for the Union Pacific Railroad as it races west to join the Central Pacific. Will's archenemy, Paddy O'Hannigan, is determined to carry out his vendetta to kill Will, Will's uncle, and Homer Garcon, all of whom he blames for his own troubles. Paddy is also desperate for money and sees a chance to get rich when he learns that Leland Stanford, president of the Central Pacific Railroad, is bringing a golden spike to the ceremony to mark the completion of the first transcontinental railroad. Paddy's plan to steal the spike will have grave consequences for Will and his friends...if they can't stop him in time.