Initial cast, pictured: (l to r): Nick Stokes (actor is George Eads), Greg Sanders (actor is Eric Szmanda), Sara Sidle (actress is Jorja Fox), Gil Grissom (actor is William Petersen), Catherine Willows (actress is Marg Helgenberger), Warrick Brown (actor is Gary Dourdan), Capt. Jim Brass (actor is Paul Guilfoyle) and Dr. Al Robbins (actor is Robert David Hall).

This series has two spin-offs:

CSI: Miami and CSI: New York.

CSI: Crime Scene Investigation is an innovative, fast-paced drama that follows a crew of forensic investigators on the appropriately named "graveyard" shift at the top non-FBI Forensics lab in the country, located in Las Vegas, as they solve crimes by analyzing evidence with advanced forensic tools. Many of the shows are loosely based on real-life events, police cases, and situations.

The crew, headed by Gil Grissom, the senior investigator and the shift supervisor devoted to finding the truth through the latest forensic methods combined with old-fashioned research and intuition. Alongside Gil is Catherine Willows, a single mother struggling to balance her home life with the rigors of her demanding job as Gil's second-in-comand; Warrick Brown, whose knowledge of the gambling world helps the Las Vegas based crew, even as his addiction to it occasionally gets him into troubles; Nick Stokes, a self-proclaimed ladies man with an objective to find the wrong-doers; and Sara Sidle, the newest, outspoken member who often lets her troubled past get in the way of her job. The crew works along side Captain Jim Brass, the former head of the graveyard shift turned captain; Greg Sanders, a quirky lab tech (later switching to a field operative); and medical examiner Dr. Al Robbins.

This cutting-edge drama recently began its 10th season on the air, and has been the number one scripted series for four years running, and shows no sign of slowing down any time soon. Changes introduced with/during the ninth season are the loss of three cast members (Gary Dourdan as Warrick Brown, Jorja Fox as Sara Sidle, and William Petersen as Gil Grissom) and the inclusion of another in the person of Dr. Raymond Langston(Laurence Fishburne), a medical doctor with an interest in forensic medicine, who decides to take a major pay cut and join the hands-on side of the job as a CSI. With the beginning of the tenth season, Jorja Fox rejoins the cast on a steady "guest starring" basis.

The show summary is provided by TVRage.