Facing an existential threat that could bring down the entire Crime Lab and release thousands of convicted killers back onto the neon-lit streets of Vegas, a brilliant new team of investigators led by Maxine Roby must enlist the help of old friends Gil Grissom and Sara Sidle. This combined force will deploy the latest forensic techniques to do what they do best - follow the evidence - in order to preserve and serve justice in Sin City. In the premiere episode, an attack on Jim Brass (Paul Guilfoyle) kicks off a twisted conspiracy targeting the Las Vegas crime lab.

Gil Grissom and Sara Sidle come to the aid of a former colleague who is implicated in tampering with evidence. Maxine and the rest of the CSI team work the murder of a couple slain on their wedding day, following the evidence to the salacious underbelly of the Las Vegas elite.