After several victims are found dead while performing normal, everyday activities, the CSIs must find the reason as to why each of the victims remain upright after dying.
A popular young singer is found dead outside an infamous Las Vegas nightclub, leading the CSI team to uncover a link between that crime and a murder 50 years earlier.
When the team discovers a connection between a new murder and a serial killer, Grissom secretly joins the class of a criminal pathologist (Laurence Fishburne) to help crack the case.
The CSI team is shocked and saddened when, after working with Dr. Raymond Langston (Fishburne) on the "Dick & Jane" murders, Grissom announces that his time as a CSI has come to an end and offers Langston a permanent position on the CSI team.
The first day on the job for Dr. Langston turns from bad to worse when a simple burglary case quickly overlaps with a complicated arson and homicide case.
The detectives search for the murderer of FBI agent Billy Ray Jackson, only Billy Ray isn't really an FBI agent, and neither are his impressively capable partners, Miles Baker and Emma Solomon.
Langston and Nick are called to investigate a murder at a fast food restaurant and have quite a task ahead of them when they discover that much of the evidence is coated in cooking oil.
When the CSIs are called to a murder scene at a familiar motel, Nick is thrown for a loop as he pieces together three separate murder investigations that all took place at the same establishment over the course of a year.
When a seasoned sky diver is paralyzed after free falling to earth when his parachute doesn't deploy, he turns out to be linked to the strange death-by-airborne-toxins of two wealthy men with ties to Iran.
When the producer of the reboot of a classic SF show is murdered at a Las Vegas science-fiction convention attended by both Hodges and Wendy (both, unknown to each other, fans of the original show), they find a connection with each other as the team investigates the crime.
Catherine revisits one of the very first cases she worked as a CSI when the convicted felon in the murder claims the verdict was based on faulty evidence.
A series of indeterminate deaths test the deductive powers of the CSI team, who fear that a public health emergency may be in the offing. Meanwhile, a friendly rivalry over who will win an upcoming bikini contest takes a deadly turn...
A cache of missing chips from a closed down casino turn up in Vegas and a string of murders follow, leading Langston to use deadly force for the first time in his career as a CSI.