"CSI" stands for "Crime Scene Investigation Team". It is a group of criminal investigation professionals. Through objective objects such as fingerprints, hair, bloodstains, shells, footprints, fibers, debris, and corpse characteristics at the crime scene, they use the most advanced and high-tech means to analyze materials, and make reasonable inferences based on "everything is based on evidence" to finally lock in the murderer. The story of this film takes place in the glamorous gambling city of Las Vegas, so it involves many casino turmoil and the vast desert of Nevada. The CSI team members include: Catherine Velos (Marg Helgenberger), the daughter of a casino tycoon, Warrick Brown (Gary Dourdan), a black man who was once addicted to gambling, Nick Stokes (George Edes), a simple-minded person, and Greg Sanders (Eric Szmanda), a rock youth DNA identification personnel, etc., led by the experienced Gil Grayson (William Petersen), punching all the darkness in the gambling city.