Catherine and Nick become absorbed in the dangerous world of street racing after one of the illegal sport's hotshot drivers is found dead out in the desert at an abandoned airstrip. Back in town, Grissom and his crew probe the sudden death of a renowned poker player who suffered a violent convulsion in the middle of a high-stakes game with three others. It looks like natural causes, at first, but Grissom suspects foul play.
Grissom and his crew are called in to investigate the death of a young woman found in the hotel room of popular actor Tom Haviland. Haviland admits that he slept with her, but denies killing her. Grissom believes otherwise, however, after finding blood evidence on the celebrity. Then things get personal when Haviland's lawyer hires Grissom's former mentor, Philip Gerard, to find mistakes in the forensic part of the case. And, unfortunately for Grissom, Gerard finds plenty of errors to exploit.
Grissom and Catherine investigate the murder of a wealthy couple who are discovered just outside of their glamorous Las Vegas house, which was up for sale. Meanwhile, Sara probes the death of a cheerleader who is found eviscerated on a soccer field, her organs having been ingested by her killer.
Grissom suspects murder, not suicide, when the body of a dwarf is found hanging from a rope high above a stage in a casino hotel where a convention of little people is being held. Across town, Catherine is attacked at a crime scene where a man was murdered during what appears to have been a home robbery.
Grissom investigates when a woman vanishes while taking part in a magician's act. The female volunteer is placed inside the Amazing Zephyr's "Chamber of Doom" and the illusionist thrusts swords through the box. When it's opened, she's gone---and doesn't reappear in her seat as she's supposed to. Only traces of blood are left inside the chamber. Clues lead the CSIs to an eerie, decrepit mansion filled with secrets. Elsewhere, a rock star's death on a band bus appears to be the result of an overdose, but Catherine uncovers evidence that points to murder.
Fifteen years ago, Catherine helped put John Mathers on death row for the rape and murder of a coed at a nearby college. Her body was dumped in a trash bag, and two other girls found the same way were also linked to the suspect. As the episode opens, Mathers is about to be executed when he's granted a stay based on new DNA evidence. But while Catherine awaits the results of tests on hair samples found on the first victim, another girl at the same school is murdered... and discarded just like the first three - meaning the wrong man could be behind bars.
A middleweight boxing champ dies in the ring after taking a brutal beating from his nemesis, but Grissom finds evidence that points to murder. Outside, in a nearby parking lot, Catherine works a crime scene where a Los Angeles gang member was gunned down, apparently by a rival gang. Also, Nick investigates a jewelry-store robbery.
Catherine called in by a pornographic-film developer to view graphic footage from a snuff movie in which a woman is brutally slain. But the clues are scant: The murderer isn't clearly seen, the cheap-looking hotel room could be almost anywhere and the film was sent to the developer anonymously. Outside of town, Grissom investigates another killing when a body, smothered with fire ants, is found stuffed inside a large toolbox. The initial findings indicate that the person died well over a year earlier.
Distracted by an attractive passenger, an Indian taxi driver feels his cab strike something at a suburban intersection. When he gets out to check, he finds a teenage boy pinned beneath the left rear tire, apparently killed on impact. The cabbie jumps back into the taxi to call for help, but a mob of angry onlookers - all of them white - drags him out and beats him for the crime. When Grissom arrives on the scene, he discovers that the teen has been eviscerated and has stab wounds, but shows no signs of having been struck by the cab.
Grissom, Warrick, and Nick investigate the case of man who apparently was murdered and pushed off a six story building. Grissom's involvement is cut short by renewed hearing problems. Catherine looks into the murder of man outside of his regular bar.
Some bird watchers find a raven with a human eyeball in its mouth. This eventually leads our CSIs to a divorced man and his 2 children but not much else. Warrick and Grissom look into the circumstances of David's unusual and first autopsy. This takes them to a car dealership where the man worked.
Warrick investigates the drive by murder of a young girl in his old neighborhood. The girl's father is a friend and mentor of Warrick's as well. Warrick struggles to control his emotions to the point where Grissom pulls him off of the case. Nick tackles the murder of a computer company employee. The only supects are the three other employees in the building.
Catherine takes the point in the investigation of an escalating series of peeping tom incidents. The crew is racing to stop the attacker before his crimes become more serious assaults. Meanwhile, Sara reopens the dormant case of her friend, a district attorney. The DA is facing surgery to remove a bullet she got in an attack that killed her husband three years prior.
Grissom investigates the murder of two men that leads him to a new encounter with Lady Heather. Catherine is desperate to find out what lead to the near death of her daughter and why her ex, Eddie, disappeared.
A man driving with a wooden stake in his head dies in front of a casino. Grissom and Nick work to discover the 'vampire"" killer. Warrick and Catherine hunt for the killer of a NBA star's 5 year old son.
Catherine, Nick, and Sara investigate a seemingly months old body found in the mountains. Discovery of the man's identity lead the team to the world of robot wars. Warrick and Grissom look into the case of a man found murdered in an alley. Complicating their efforts, the medical examiner ""lost"" the body for 11 days. Greg helps this case by doing some undercover work.
Grissom and Catherine investigate the murder of a despised comic who died onstage, apparently after drinking from a tainted bottle of water. The case grows more puzzling when a 15-year-old boy dies in a convenience store after drinking the same brand of water. Brass reopens a woman's accidental-death case after spotting the deceased's husband in a flashy new car with a trophy date on his arm.
A murder aboard a luxurious 747 and the discovery of two formally attired teens in the desert confound Grissom and his crew in this absorbing episode. First, a horse trainer is found dead in the cargo bay of a private jet carrying 12 well-heeled passengers and a million-dollar show horse. Initially, it appears the victim was trampled to death, but Grissom and Catherine uncover evidence of foul play. Meanwhile, in the Hell's Gate section of Death Valley, Sara and Warrick probe the apparent suicide of a 15-year-old boy found under a bedspread. The investigation intensifies when a girl's body turns up a half-mile away.
A woman's body is discovered in a small press box at a high-school football field, apparently the victim of strangulation. The evidence leads investigators to two convicts, one of whom is still in prison. At the crime lab, an explosion destroys key evidence and leaves Greg and Sara injured.
Things get personal for the CSIs in the top-rated series' third-season finale, which explores the intersection of the investigators' work and their personal lives. Three masked bandits steal a safe-deposit box from a Las Vegas bank in a daring daytime heist, during which Det. Lockwood is killed. Lockwood's death provides Grissom and his crew with added incentive to find the murderous culprits. But the case really hits home for Catherine when the evidence leads to casino owner Sam Braun, who is like a father to her. Also, Grissom's hearing gets progressively worse and he seeks out Dr. Robbins for help.