The headlong adventures of an irresistible detective duo in a darkly fantastical 19th century.

1887: Gabriel Voltz is no ordinary detective. His specialty is hunting down the "Lost," heretical creatures hiding under human appearance. None of these monsters has ever been a match for Voltz's supernatural strength. But now that he's taken Rose under his wing, an orphan who's as insufferably stubborn and nosy as she is endearing, he's exposed himself to the wrath of his powerful employer. When the Brotherhood sends him to Finistère to solve a mysterious murder case, Voltz has no choice but to take the teenager along for the ride. The investigation promises to be more hazardous than expected, as all leads converge on the mysterious Porte-Vent estate...