A peaceful camping trip devolves into a desperate fight for survival when two families are hunted by a malevolent mother and son in the remote California mountains. The idyllic escape of the Miller and Johnson families shatters when they encounter an ancient, malevolent woman wielding dark powers and her feral, violent son. Trapped in the wilderness with limited resources and no escape, they must confront the primal terror that stalks them, a force driven by unholy rage and a brutal, insatiable hunger. The narrative unfolds with relentless pacing, focusing on the escalating dread and the raw struggle against a supernatural and physical threat.

Richard Laymon's "Dark Mountain" is known for its visceral and relentless horror, characteristic of his signature style. The novel plunges readers into a terrifying scenario where ordinary families face an unholy threat in a remote setting. Reviewers often note Laymon's ability to build intense suspense and deliver shocking moments, making this a gripping read for fans of extreme horror. The narrative's focus on primal fear and the brutal nature of the antagonists contributes to its reputation as a disturbing and effective thriller.