Pecos County Sheriff, Cody Johnson and Lieutenant, Billy Parker come across five year old, Olivia D'Angelo, an abused child in a state of Selective Mutism, wandering alone in Texas' Chihuahuan Desert. During the hunt for the man who may be responsible for her being there, Olivia's mother, Francis, who Cody later learns is a suspect in the murder of her husband, Tony, is found buried in a shallow grave halfway up the Glass Mountains. Fears of a serial killer on the loose is sparked by the discovery of the skeletal remains of a young female in the same vicinity during their search for clues....