A deadly bomb explosion at a Vegas office building sends Grissom and the CSI team in search of a serial bomber. Their primary suspect is the building's overly helpful security guard, who knows more than he should about blowing things up.
Grissom and Catherine investigate when a leg is found severed from a body in a lake. Meanwhile, Sara and Nick investigate a fraternity pledging gone terribly wrong.
Grissom and Brass track down a serial killer who stages his murders so that they appear to be suicides. Meanwhile, Willows and Brown investigate a robbery and a homicide.
Catherine violates department protocol when she takes the case of a rape accusation against her ex-husband. Meanwhile, Warrick and Sara search for the missing bullet that will either exonerate or indict a cop for murder.
A couple leaving a restaurant on their anniversary are killed in the street, and their car is stolen. The crime scene is compromised when it rains shortly after the CSIs arrive.
The son of an entrepreneur who helped build Las Vegas is found dead of an apparent drug overdose, but the clues at the crime scene lead the CSI team to suspect that his death has been staged, and that they are looking for a murderer - or two.
Grissom, Nick and Warrick take the case of a jogger who was killed by a wild animal in the park. It gets complicated when they discover that the jogger had his liver removed after he was killed.
On the day Grissom has to evaluate his team, a head is found in the trunk of a car. While Gil and Catherine work on the head, Sara and Nick investigate a body in the desert that's missing its head.
Grissom investigates a possible suicide at a high-profile construction site, while Catherine and Nick look into the case of a young boy found dead at his therapy session.
A battered body tells the CSI team a troubling story, and in the course of their investigation, the evidence not only leads them to those responsible for the young man's death, but also reveals surprising information about Grissom's personal life.
Grissom, Sara and Brass are called to Sparks State Psychiatric Hospital when a nurse discovers one patient murdered with his skull smashed in, and another huddled in the opposite corner, covered in blood.
When Jim Brass receives a rare phone call from his daughter Ellie, he takes emergency leave and travels to Los Angeles to help her find a friend who has disappeared.
Grissom is called to investigate the murder of a 17-year-old in a casino penthouse. The entire team gets involved when it's discovered that a kidnapping took place along with the murder.
Sara and Greg investigate the death of two naked students at WLVU, who clearly died after a night of lovemaking. What is not clear is what turned their bodies pink, after carbon monoxide and cyanide have been ruled out as cause of death.
A lonely and frustrated Catherine meets the wrong man in a bar, but doesn't admit to the encounter - even when he turns up as the lead suspect in what may be a double homicide.
One night, four cases. Grissom and Brass get a stolen hummer and a taco stand. Warrick gets a dead car show girl. Sara and Greg get a dead bodybuilder. Nick gets a dead boy found on a bench.
Grissom, Sofia, Sara and Greg investigate the disappearance of a woman coming home from a night out with a friend after her abandoned car is found on the edge of a highway.
A woman's head is discovered in a newspaper dispenser, and when Dr. Robbins does his post-mortem he finds a startling clue - a dead snake resting in the victim's mouth.
Grissom is shocked to discover the prime suspects in his ongoing homicide investigation shot to death in their house. But what is more surprising is that their murder points to an inside job.
When Grissom and Warrick arrive at a burglary scene, they are shocked to discover the mummified corpse of an elderly woman locked in a closet from a prior home invasion.