When Xavier Garza awakensin the back of his employer's buckboard wagon, with Thomas Wilkins following on horsebackhe learns that after the massive Atahsaia knocked him aside, leaving him unconscious, it had fled the cabin with his wife and baby son.
Xavier and Thomas are about to begin a relentless hunt through some of Colorado's rugged back country, leading eventually to a confrontation with the man-beasts in and around the biggest, deepest, blackest, most-threatening canyon either of them had ever seen.
What will the men have to do in their efforts to survive? What lessons will they learn about mercy and obedience?