Iron Horses Can't Be Broken. Galvanic Century, #6

Can you ever truly atone for the sins of the past?When British detective Alton Bartleby mustered out of the Royal Navy a decade ago, he saw his family with new eyes. Saw how his father's love of drink and his sisters' and mother's lavish lifestyle was quickly draining the modest fortune he'd managed to acquire. Perhaps rashly, perhaps justifiably, he had his father committed and the women exiled to America, arranging a wealthy husband for his elder sister Sarah.
He spent the next ten years restoring his family name and fortune, while working as a consulting detective in London. He didn't think of them again. Until now. Until his wife Aldora booked them a holiday in the American Southwest, to the small Arizona town he'd forgotten. To the territory of Robert Koning, a brutal thug once promised a young woman's hand, a murderous bastard left at the altar when Sarah ran off with a Zuni mechanic, leaving a theft and a murder in their wake.
Aldora had intended to force reconciliation with his sisters. Instead Alton finds himself forced to hunt down his missing sister for the man she left behind. Can he save Sarah from the monster that pursues her, or will all of the Bartlebys end up in unmarked graves in the desert?