When the university students Paula Levine and Trip Wilmont are found dead on the floor after having sex in Trip's dormitory room, Grissom, Sara, Greg and Capt. Brass investigate the case. Grissom leaves the case since he has to go to the court and Sara and Greg use the monoxide carbon detector to look for a source, but they do not find any monoxide carbon in the room. Meanwhile, Brass talks to his next-door neighbor Zack Capola, who says that Trip and him were just mates, not friend. Sara and Greg proceed the investigation. Meanwhile, Catherine, Warrick and Nick join to David Phillip in the middle of a crop circle to investigate the death of a man. In the autopsy, they learn that the victim has urinated in his underwear. When the CSI team locates the owner of the helicopter that was in that area, they learn what has happened to Kevin Staniland. Meanwhile, Det. Louis Vartann finds that no investigator is available and Conrad Ecklie is forced to go with him to the Tangiers since there is a dead body needing to be processed. They learn that the victim is James Billmeyer from New Jersey and Ecklie requests the shoes of the woman that found the body since she stepped on the blood. When James' body vanishes from the morgue there is a further investigation.

After a massive shootout between the LVPD and a Latin American mob gang, the CSI team have to find and process hundreds of bullets to determine exactly what happened.

The CSIs continue to process the evidence collected from the high-speed chase. They must also find the bullet which killed a police officer to determine who shot him.

A reverend is found dead on former CSI detective Warrick Brown's grave, and the team discovers several connections between the case and Brown and his family.