Grissom and crew are called in after high roller Tony Braun, a known drug addict, is found dead in his house by a gardener. Since drug paraphernalia is discovered near his body and it is also determined that he had recently inhaled heroin, the cause of death is at first thought to be an overdose. But further examination of the corpse reveals that Braun had been restrained at some point with duct tape, leading Grissom to believe that the victim was forced to ingest lethal amounts of heroin and, perhaps, other drugs.
Grissom and Catherine investigate the apparent violent death of a woman found in a sandbox. Warrick and Sara are called to a crime scene to investigate a shooting, which initially appears to have taken place during a robbery.
Grissom and Sara are called to the crime scene when two murder victims are found hidden in pipes at a construction site in the middle of an alfalfa field, while Catherine and Nick investigate an ostensible hunting accident.
Grissom's nemesis, serial killer Paul Millander, reappears and claims a third victim in this gripping episode. The latest slaying matches Millander's previous killings in that it recreates his father's murder. The killer's next target was born Aug. 17, 1956...which just happens to be Grissom's birthday.
Grissom investigates the murder of a Las Vegas photographer whose remains were dumped at a nearby body farm where CSIs routinely study corpses, and his findings reveal that the man was apparently shot to death even though there are no bullet fragments in the body.
Grissom investigates the murders of four monks who were shot point blank while chanting in a Buddhist temple; Catherine reopens a cold case in which her best friend was murdered, after the man convicted of the crime claims he's innocent shortly before he dies.
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.
Jane Galloway lives in fear. Her doors are triple-locked. Every shade is drawn. The bathroom window is nailed shut. An alarm system is activated. Who killed Jane, and how could the murderer have possibly entered, and left, the house?
Grissom and Catherine investigate the stabbing death of an 80-year-old woman who lived in a run-down house full of cats; Nick and Sara comb through the remains of a car bombing that was, apparently, a murder plot gone awry.
Grissom and his crew handle their highest profile case to date when the city's former chief of detectives is slain execution-style in his house following a wild party. Missing from the residence are the chief's trophy wife and their 7-year-old daughter. Catherine and Warrick follow the trail to Miami, and soon enlist the help of Horatio Caine.
Season Finale. The CSIs investigate when the body of an unidentified young woman is discovered stuffed in an overturned shopping cart near a freeway underpass. Her horribly disfigured and partially decomposed face is a nightmare of blood, scabs and scars, as if she'd been shoved into a fan. A huge circular hole dominates her left cheek. Someone not only wanted her dead, Grissom reasons, but ""they wanted her ugly."" Adding to the mystery are the cart's other contents: an expensive handbag, fashion magazines and a leather day planner with notes written in code.