Royce Harmon was murdered 3 months ago in a scene staged to look like a suicide. Now another murder has taken place. Whoever the killer is he has a thorough knowledge of forensics, he purposefully has left evidence, and has baffled Grissom and his team. Warrick and Nick investigate the case of a man who went over a cliff in his car and is now unconscious.

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. It gets more mysterious when the car is found and it becomes a new crime scene. Catherine looks into the collapse of a city owned residence that kills three elderly women. She runs into problems with the city engineer responsible for the building.

A bus carrying 23 passengers from Los Angeles to Las Vegas crashes less than 40 miles from its destination, killing nine people. Tthe CSIs soon discover that a recent parolee was on the bus, but is now unaccounted for.

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.

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.

During Vegas's latest Heat wave of triple digit temperatures, Gil and Catherine investigate a baby locked in a car. Warrick investigates a man dead of an apparent heat stroke in his house. Nick and Sarah investigate a woman's body found floating in the lake with a blow to the head.

A violent murder in a casino parking garage and another episode in the police interview room lead the CSIs to one shocking discovery after another. The case involves a missing woman, a long dead body and a missing child.