After an earthquake leaves Danny trapped and alone, his claustrophobic nightmare only gets worse when something truly horrifying emerges from the fissures in the ground, forcing him to engage in a brutal fight for his life and his sanity.
Based on actual events of American serial killer Edmund Kemper, who murdered his grandparents at age 15 and, after being paroled for that crime, killed eight women in 1972 and 1973 including his own mother.