In a gaslamp city where the dead can be briefly reanimated, a reclusive undertaker's apprentice who hears the final thoughts of the deceased discovers a brilliant inventor's consciousness trapped inside his own clockwork heart. Forced into a reluctant partnership to solve his murder before his power runs out, their psychic investigation forces her to confront the walls around her own heart, leading to a love that defies the very boundaries of life, death, and machine.