The Hand of Osiris by Frank Cavallo

Ye serpents, Ye generation of vipers,
How can ye escape The damnation of Gehenna?
- Matthew 23:33

1879

The outlaw Jedediah Sykes has just killed the wrong man, the nephew of a powerful rail baron. Now he’s on the run and the bounty hunter Jacob Hatcher is hot on his trail with a group of hired men and Apache guides. But when the guides refuse to go any further, warning that the lands ahead are cursed by an ancient and nameless evil, Jacob is forced to go the trail alone–a trail that leads him to a town, a dark paradise of sin and vice called Gehenna.

Hatcher and Sykes soon become entangled in the mysteries of Gehenna’s peculiar denizens: a fire & brimstone Jesuit who’s preaching to a city of lost souls, and a shadowy figure who rules over the town like a living god. When one of them makes a choice that threatens to damn them all, the rest must work together to find a stolen key that can unlock the domain of the dead. And in their search, confront not only their own demons, but the hidden horrors of Gehenna itself..