The continuing story of the forensic heroes of the las vegas crime scenes as they untangle the evidence behind police lines bagging and swabbing every morsel of evidence to nail the bad guys a tumultous year for the vegas crime lab as sara sidel returns to help bring down a viscious serial killer who is wrecking havoc across the city whilst delivering a clear message to the team working to bring him down raymond langston promoted to a level 2 csi takes on a new case