Victorian England. When her murderous father escapes from an institution, a young girl is forced to flee to safety with secretive pickpocket Anna. Disguised as a boy called Viktor, and drawn into Anna's mysterious activities, she is catapulted into a strange investigation, and learns that Anna may be able to help her uncover the mystery of her mother's disappearance. As she and Anna find friendship, Viktor's disguise brings empowerment and safety, until a tragedy forces her to take on a new identity in order to survive a world full of supernatural threats.