Hester is a character with a prominent facial scar that drives her motives for much of the story, and her interactions with other characters lead her to openness and personal growth.

Valentine is a charismatic and ambitious antagonist, whose past and present actions impact the lives of several central characters.

Katherine is Valentine’s daughter, who starts the story in a life of comfort but evolves in her understanding of the world and those around her.

Crome is the authoritative Lord Mayor of London and represents the novel's main threats through his unyielding quest for power.

Anna is a skilled pilot who stands against the moving cities and influences the protagonist’s journey with her perspective.

Grike is the last existing Stalker, linked to Hester’s past, and plays a significant role in her emotional journey.

Bevis is an apprentice Engineer from the lower tiers of London, whose experiences highlight the inequalities within the city's society.

Pomeroy is the Deputy Director of the Guild of Historians who assists in crucial events towards the story's climax.

Although deceased, Pandora is a significant figure whose past actions and connections influence several key plot points and characters' motivations.