After decades of waiting, a man exacts revenge...
Tropes:
- Abusive Parent: Gregory Hall was this to Robert and Shawn. When Robert asked what happened to Rita, he received a beer bottle to the head. It's not quite mentioned what he did to Shawn.
- Borrowed Catchphrase: Subverted when Francis tries to borrow Gordon, James, and Henry's "disgraceful, disgusting, and despicable" catchphrase to describe Sir Topham Hatt allowing Peter to pull passenger trains, but James cuts him off at the second syllable of the latter word.
- Cliffhanger: The episode ends with Mr. Zorro's killer breaking into the munitions factory in Cros-Ny-Curin.
- Cold Open: The third episode to have it, we're shown events that take place during "Sabotage."
- Downer Ending: Peter and Mr. Zorro are killed by a act of vengeance and even worse, the person who murdered Mr. Zorro is not done yet.
- Driven to Suicide: Robert's mother did this after her family's house was foreclosed.
- Everyone Has Standards: Francis gives Peter grief for his war criminal disposition, but when Peter dies, he also mourns him.
- Killed Off for Real: Peter and Mr. Zorro.
- Laser-Guided Karma: Sir Topham Hatt initially wanted Peter's colleagues to rotate the fuel deliveries, but after Francis bad mouths his decision to have Peter pull passenger trains, the Fat Controller has the class 46 pull the fuel trains exclusively.
- Moral Myopia: Francis takes issue with Peter's retort about having unpleasant conversations with the diesel, but conveniently forgets that engines have unpleasant conversations with him all the time.
- Mythology Gag: "Pot calling the kettle Spamcan?" (Also counts as a Call-Back, due to James and Henry calling Francis this in "Dieselisation".)
- Rule of Three: After the deaths of three Midis - two engines and their former director, Donald hopes the murder spree will be over.
- Surprisingly Realistic Outcome: One for Mr. Zorro. While he might have improved considerably and revealed his greater depths as a person, growing into a genuinely decent man, it doesn't compensate for the truly awful things he's done prior to this growth, and his past actions as a ruthless schemer during the early days are not going to be forgotten by those he hurt. In this case, the children of the poor woman he denied help (and who committed suicide as a result) end up growing up desiring vengeance against him, and they take it without hesitation.
- You Do Not Want To Know: Donald misses an opportunity to ask Robert about his father, but Barry tells him that, given the circumstances, he's better off not doing so.
