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

Author Philip Reeve's series of Mortal Engines novels have an undeniable political undercurrent, detailing the global devastation caused by the "Sixty Minute War," waged with nuclear and quantum energy-based weapons.

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Sticking relatively closely to the series' messages in his adaptation, director Christian Rivers brings to light nearly all of the author's world views, and in doing so, he shapess 2018's most political film.

Immigration

Spurred on by the villainous Thaddeus Valentine (Hugo Weaving), mobile London is a predator city, which raids the post-apocalyptic landscape raiding resources for others. Many Londoners are elitist, and as we see the caste system within the city's society, it becomes clear how xenophobic most of them are. They don't want outsiders, unless they're to work menial jobs, such as the city's engine room.

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Rivers makes a big statement on immigration, showing how London resists offering aid to those who need it, unless it can benefit the city. Ironically, London's citizens become refugees themselves when the city is defeated by the Anti-Traction League. That results in the League holding the citizens at gunpoint at the Great Wall, before opting to welcome them. They even take in the ones with a colonizing mentality, as they have nowhere else to go.

Human Trafficking

When protagonists Hester (Hera Hilmar) and Tom (Robert Sheehan) escape Valentine's reach, they're taken in by a small, underground train. However, they awake as prisoners, and are traded off at a slave market to cannibals.

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They're rescued by Anna Fang (Jihae), one of the League's generals, who educates them about the outside world and how predator cities have devolved. She had been a slave herself, but escaped to join the League. It's now her mission to stop slavers, who flourish in a society based on scavenging, and preying upon the weak, whether they be other cities or other people.

Humanity's Effect On The Planet

Mortal-Engines-Hester-Shaw-London

Mortal Engines leans into climate change as well, as Tom, a historian and scientist, tells Hester about the effects of the war. There's little to no rainfall, and hardly any vegetative areas, resulting in a wasteland of mankind's creation. As Tom recounts humanity's selfish ways, he's inclined to join the League to make a difference and also to stop traction cities, as he sees the a continuous burning of coal for their engines as sealing the fate of the planet.

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Another issue is the draining of Earth's resources. While there are no longer any forests, there also aren't any oil fields from which to extract fuel. Humanity has bled the planet dry, which is why the predator cities are on the move.

Terrorism

Mortal Engines also speaks to European unions that formed and fell within the League, even referencing those like London that broke away in a Brexit-like move. Those became the predator cities. Tom also recalls how the world superpowers like Russia and the United States underestimated other countries that stockpiled weapons against them in the war. When the dust settled, those who survived scrambled to find new alliances.

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The remaining governments forged alliances and plotted against each other, but ultimately, friend became foe as everyone had to fight for diminishing resources. That's why Valentine became a terrorist leader, building a network of spies and soldiers to recover old quantum energy tech: so he could lead a coup, weaponize London, take down the League and have free rein across the rest of Europe.

Directed by 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.