Strong women, ancient magic and the walking dead make for a heady mix. In Michael Merriam's tale, seven women are called to protect a small mining town in the New Mexico Territory, Tierra De Cobre, against an evil that has killed or stolen the town's men and is twisting the souls of the townswomen. The Sihuanaba is part siren, part shapeshifter, possessed of the body of a beautiful woman, her face a horse's skull with flaming eyes. Once she is freed from her copper prison in the mine, she feeds off the miners to regain her strength, then consumes or twists all the men who come to rescue them. Maria Garcia, recently widowed and quietly fierce, has the answer: hire women to fight the monster. And they do. Taking the classic Western "The Magnificent Seven" as a jumping off point, the town's defenders are assembled, all women from wildly different backgrounds, united by one mission: to defend the town and defeat the Sihuanaba. All the odds are against them, the price of failure is death or worse and all they have is each other.