The Affinity Bridge by George Mann

Set in an alternate Victorian London, a fastidious investigator and his resourceful young assistant are drawn into a tangled case of missing children, murderous automatons, and a conspiracy that blends cutting-edge steam technology with occult ideas. As they follow clues from gaslit streets to smoky factories, they must outwit a charismatic but dangerous engineer whose experiments threaten the city's social order and innocent lives, forcing the pair to confront moral compromises and the human cost of progress.

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