: While the investigation unfolds, the Murdochs are seen navigating the challenges of parenting their young daughter, Susanna.

The episode features the regular series cast alongside several guest stars: : Detective William Murdoch Daniel Maslany : Detective Llewellyn Watts Jonny Harris : Constable George Crabtree Hélène Joy : Dr. Julia Ogden Thomas Craig : Inspector Thomas Brackenreid Claire Armstrong : Gert Dotson (The Killer)

The mystery begins when Watts, now working as a private investigator, informs Detective William Murdoch about a vagrant's death at a rail camp. Watts had been hired to find this man because he was the heir to a significant family fortune. When a second man is found murdered, Murdoch suspects a "sequential killer" is at work and enlists Watts and Crabtree to "ride the rails" undercover.

The investigation reveals that the victims were part of a group that had murdered a legendary hobo known as "Gentleman Jones" years earlier in Nebraska. The killer is eventually revealed to be Gert Dotson, the wife and former traveling partner of Gentleman Jones, who sought revenge against the men who killed him.

: Pasty (A hobo whose song provides crucial clues) Notable Themes and Subplots