When a group of bird watchers sees a raven with an eyeball in its nest, the CSI team investigate the case. They trace a radius from the nest and using the evidences, they find the location where the corpse may have been dumped. Catherine, Sara, Nick and Capt. Brass find the body and they identify the body. The prime suspect is the ex-husband of the victim. Meanwhile, Grissom, Warrick and Dr. Robbins find that the car seller Fred Stearns is not dead but dies later. They suspect that one of his colleagues may have killed him.

When a private jet lands after a party, they find the trainer Lori Hutchins dead apparently stomped by the horse in the cargo bay. Grissom, Catherine, Nick and Capt. Brass investigate the case. The horse is in quarantine and the veterinarian Dr. Stevens help Catherine to collect material from the animal. They interview the owner of the jet, guests and crew and find two tranquilizers dart in the cargo bay. When the horse mysterious die, Dr. Robbins make the autopsy and they learn what happened in the flight. Meanwhile, Sara, Warrick and Det. Lockwood investigate the suicide of a teenager in the middle of the desert. When they find a second body dead in the same circumstances, they believe it was a kind of "Romeu and Juliet" pact of the younger. Then they identify the couple, Toby Wellstone and Jill Frommer, and interview her mother trying to understand why they died in a distant place and separated from each other.

When a delivery boy finds a severed head with the hair ripped off inside a newspaper stand, Catherine, Nick and Det. Sam Vega assume the case. In the autopsy, Dr. Robbins pull out a snake from her mouth and finds the serial number of her bridgework. The victim is identified as Veronica Juarez, and the investigators find a diploma from a university on the wall. They believe she is a gangbanger and they see a poster of the band Extremo. Nick and Det. Vega visit the club where Extremo is playing and they identify the victim as Carla. Soon they learn that the song that Extremo is playing is a ten-year-old narcocorrido that describes the way Veronica was murdered. Meanwhile, Greg, Sofia, Warrick and Capt. Brass investigate the murder of a man wearing and expensive suit shot in the head in the driver's seat of a handicap van. They identify the victim as Vincent Decarlo and they find that the victim was shot from a wheelchair. Soon they learn that the wheelchair belongs to Bonnie Bakerset, who lives in a nursing home, and a nice salesman has sold many things to Bonnie that has just died.

A man is found in a dumpster with a very full stomach. A divorcing couple are found dead together on the floor of their house, where their dog becomes the first suspect.