Lirael, an orphan raised in a London workhouse, possesses the rare gift of a "Steam Savant"—a single touch can bring dead machinery back to life. Summoned by the noble Bresman family, she finds herself targeted by Vivienne, the fake heiress who schemes to destroy her. Enrolling in the Royal Academy of Magic and Mechanics, Lirael stuns everyone with her brilliance but is framed by Vivienne, who allies with the mad scientist Dr. Draven to plant black steam devices. With the help of the legendary Perpetual Heart, Lirael clears her name and uncovers the "Great Boiler"—an ancient black steam device sealed beneath the Academy. Racing against time, she gathers four Elemental Cores to re-seal the Boiler before the full moon. In a final aerial battle, Lirael unleashes her ultimate form as a Steam Savant, purifying the black steam behemoth and saving London from destruction.
