The CSIs investigate the death of Maria Flores, a fourteen year-old girl who was shot and killed in the middle of a large rave in the desert. Based on evidence at the scene and witness testimony, the CSIs determine that Maria was with another girl, and both were being pursued by Maria's eventual killer. They then find Jacinta Flores, Maria's sister, being cared for by a nurse who was at the rave. Both Maria and Jacinta were victims of extreme sexual abuse and neglect, to the point where Jacinta is fearful of everyone and everything - even sunlight. To make matters worse, Jacinta is illiterate and her tongue was forcefully removed by her captor, making communication with the CSIs nearly impossible. Russell and Morgan learn that Jacinta was abducted when she was only four years old, meaning that she's suffered well over a decade of unimaginable abuse. They then get in touch with her biological father, Adrian, who comes to get her from the hospital. Meanwhile, the rest of the team pieces the clues together and hunts down their lead suspect, a cattle truck driver named Ollie Ruiz. Despite incriminating evidence to the contrary, Ollie informs the CSIs that he's never seen the girls, and a piece of evidence Ollie provides leads them to the true killer - Jacinta's own father, Adrian Flores. The CSIs and LVPD manage to locate Adrian's compound and arrest him before he can harm Jacinta any further.