WARNING: The following article contains spoilers for Mortal Engines, in theaters now.
The post-apocalyptic adventure Mortal Engines follows the tragic journey of Hester Shaw as she seeks to exact revenge against the leader of the mobile city of London, Thaddeus Valentine. Along the way, she teams up with London outcast Tom, Anna Fang and the the Anti-Traction League in an effort to halt the moving predator cities that scour the barren landscape for resources.
The film ends with London shut down after attacking the Great Wall of the Shield, a key hub of the League, which stands in opposition to the mobile cities. As Hester (Hera Hilmar) and Tom (Robert Sheehan) then set off on a romantic trip to see the world, the League takes in London's inhabitants and looks ahead to a new world order. With all of that unfolding in the finale, there are a few directions a sequel can follow.
REBUILDING THE WALL
After London uses a quantum-energy weapon called Medusa to break down the Shield's wall and try to invade, Tom and Hester defeat Valentine (Hugo Weaving), and leave him for dead. A sequel obviously could focus on rebuilding the Wall and how this new society is shaped following the League's acceptance of the London refugees.
It could shape an interesting dynamic, because so many Londoners supported Valentine, and only shifted allegiances when he tried to turn the city into a battering ram. Some loyalists could still exist, serving as spies for like-minded tyrants, and trying to take down the League from the inside.
NEW EVIL TRACTION CITIES
A sequel could also follow the second novel in author Philip Reeve's series, Predator's Gold, by diving deeper into the vicious traction cities like Arkangel. This city was famous for owning slaves, and is considered to be even worse than London. Anna (Jihae) was actually enslaved there, and she warned how dangerous it is. Arkhangel can move across snow or dry land, making it a relentless slaver capital with which Valentine's supporters could align.
We also see other Scavenger Cities try to kill or enslave people in the film, with Tom and Hester barely escaping. They move on the fringes and in the marshlands, disguised as the terrain, and hearing that London almost breached the Wall could certainly be a reason why they decide to strike the weakened Shield, ravage their resources and destroy any attempts at peace.
THE ADVENTURES OF ANCHORAGE
Throughout Mortal Engines, the ghost of America looms large. It was a major world power in the "Sixty Minute War," developing weapons of mass destruction such as the Medusa. Tom has been obsessed with exploring North America since he was a kid, and in Predator's Gold, he gets the chance.
A sequel can follow that storyline by bringing into play another traction city, Anchorage. This city took him and Hester hostage, thinking they stole Anna's ship, but when everything was cleared up, they ventured to America to mine resources to defeat the Predator Cities. Apart from going there to unearth dark secrets of the initial war, a sequel can also pit Anchorage against Arkangel. The latter wanted to raid Tom and Hester's new home in Predator's Gold, as it was a peaceful trading hub ripe for the picking.
THE DEAD RETURN
In Mortal Engines' finale, when Tom rescues Hester from Valentine's airship, it crashes just in front of London as the city barrels toward the Wall. However, Tom shoots out the engine, causing London to come to a grinding halt before it hits the structure. In the process, its wheels crush Valentine's aircraft, but at that moment, the camera zooms out, leaving it unclear whether he's actually killed. That easily sets up the villain's return, allowing him to operate in the shadows, controlling agents on the inside of the Shield.
A follow-up can also dive into Anna's resurrection, a la Predator's Gold. There, she returned as a Stalker (a cyborg implanted with human memories), corrupted to hunt Hester and Tom. We already saw the Stalker known as Shrike, and with Anna's dead body still in London after Valentine stabbed her and she fell to her death, there's no reason she can't be turned into a Stalker too. Valentine already has a relationship with the folks making them, so Anna could be transformed into his brand-new secret weapon.
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.