Mortal Engines' High-Octane Ending, Explained

Mortal Engines

WARNING: The following article contains spoilers for Mortal Engines, in theaters now.

An adaptation of Philip Reeve's series of steampunk-fantasy novels, Mortal Engines is set in a post-apocalyptic world in which humanity has formed mobile "predator" cities, like London, hunt down and absorb smaller settlements in a fight for resources. The film follows the adventures of Hester Shaw (Hera Hilmar) as she tries to kill London's tyrannical leader, Thaddeus Valentine (Hugo Weaving).

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Not only did the greedy Valentine kill Hester's mother, but he's now trying to take down the Wall protecting The Shield, a society that influences the peace-seeking Anti-Traction League, which has developed alternative, stationary settlements. As their rivalry builds to a showdown, the finale doesn't only end up changing the course of Europe, it also unravels a dark secret about Hester's past that will undoubtedly alter her destiny.


The "Sixty Minute War" was a nuclear arms race in which the world powers destroyed each other. America is left uninhabitable while Europe and Asia barely survived. Young historian Tom (Robert Sheehan) reveals the main weapon Europe used was called Medusa, a quantum-energy blaster that now longer exists.

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When Valentine tries to kill Tom to keep secret that he murdered Hester's mom, Pandora, Tom and Hester align with Anna Fang (Jihae) and the Anti-Traction League. However, Valentine's spies have already raided Tom's old technology stash in London, and have rebuilt Medusa. With the resistance at the Wall trying to come up with a plan, Valentine begins blasting the structure away so London can raid what's behind it.

However, when Valentine killed Pandora, she was able to slip her daughter a trinket that contained the one thing that could shut down the Medusa: a USB key called a crash drive. Tom pilots Anna and Hester to London, where they sneak into Valentine's control room. There, Valentine takes on Anna, and kills her, only to be distracted long enough for Hester to use the drive and stop the Medusa, rendering the city powerless without its weapon of mass destruction.


Hester tries to escape, but ends up battling with Valentine aboard his getaway aircraft. She can't resist the urge to exact revenge, not only for her mother but also for Anna. Hester scars Valentine's face, mirroring the wound he left her with years earlier, when he killed her mother.

That spurs him to spill a dark secret, goading Hester into recalling repressed memories. Early on, Valentine was seen as Pandora's confidant, a historian who helped her to archive her archaeological collections. But when she found a suitcase with the elements needed to recreate Medusa, he killed her, burned the house down and left Hester for dead.

But Hester recalls also the loving moments Valentine and Pandora shared. She panics as Valentine tells her, "Your mother never told you, did she?," confirming her greatest fear: Valentine is her father.


Without the Medusa, Valentine's last, desperate act is to ram London into the Wall in an effort to break it down, not caring whether it kills everyone inside. After all, he was on his plane (although he was unaware Hester would attack him there). With Hester busy, Tom uses his knowledge about London's great engine, having lived there his entire life, takes Anna's jet and blows the machine apart.

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That causes the city to stop just outside the Wall, and everyone inside being taken in by the Anti-Traction members. It's a tense moment, because they know half of London wanted to pillage their home, but seeing as the Londoners realize Valentine was using them, they come to their senses. Valentine's kind daughter, Katherine (Leila George), leads her people now, and the Shield, while skeptical at first, eventually lowers their guns to allow the refugees in, believing compassion is the only way forward.

Tom then rescues Hester from Valentine's plane, leaving the tyrant aboard the damaged aircraft to crash and burn, and seemingly be crushed by London's wheels. However, they decide they don't want to become refugees, and opt to take Anna's jet, travel and explore their love together.

Directed by frequent Peter Jackson collaborator Christian Rivers, Mortal Engines stars Hera Hilmar, Robert Sheehan, Hugo Weaving, Jihae, Andy Serkis, Ronan Raftery, Leila George, Patrick Malahide, and Stephen Lang. The film is in theaters now.

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