LitCharts assigns a color and icon to each theme in Mortal Engines, which you can use to track the themes throughout the work.
Social Class
Sacrifice
Dangers of Technology
The Importance of History
Prejudice and First Impressions
Friendship
Summary
Analysis
Just in time, Tom stops the scavenger girl from stabbing Valentine in the heart. She squirms away from Tom and flees, while Valentine orders someone to catch her. Tom goes after her as she heads for the furnace district. When she hesitates at an intersection, Tom reaches out and manages to pull off her pack. He gets a look at her face and sees that her face has a giant scar and that she only has one eye. She asks Tom why he didn’t let her kill Valentine. When Tom protests that Valentine is a kind man, the girl says he should ask Valentine what he did to Hester Shaw. With that, the girl (who seems to be Hester Shaw herself) jumps down a garbage chute.
In fiction, outer physical deformities often symbolize an evil inner nature, but Mortal Engines subverts this idea. This passage plays with the stereotype that a character who is “ugly” on the outside will also be ugly on the inside, reflecting Tom’s belief in this conventional way of thinking. But when Hester mentions that Valentine may have done something awful, this hints that perhaps appearances are misleading and Valentine is not as heroic as he seems on the surface.
Active
Themes
Quotes
When Valentine catches up, he asks what happened to the girl, and Tom tells him that she’s dead, even though it was too smoky to see what really happened to her. After some hesitation, he brings up how the girl mentioned her name was Hester Shaw. At this, Valentine just smiles sadly. All of a sudden, Valentine shocks Tom by pushing him down the garbage chute where Hester went.
This passage captures Tom’s conflicted feelings. On the one hand, he still doesn’t trust Hester enough to believe her fully. On the other hand, something Hester said resonated with him, and he can’t help asking Valentine about it. When Valentine pushes him, Tom learns very suddenly that perhaps Hester was right after all.