The third part of the CSI crossover trilogy:
Ray Langston is back in Las Vegas and still searching for Madeline Briggs after trying to find her in Miami and New York. At the same time, a local weather girl, Deedee, is found dead outside the Tangiers Hotel & Casino, dressed as a prostitute. When the team examines her, they discover Madeline's blood on Deedee's earring and an equally important tattoo. They theorize that Deedee and Madeline may have lived in the same place and shared the same pimp, so they go to a nightclub and spot another prostitute, Diane, with the same tattoo as Deedee. They arrest her on a bogus charge but get a lead when she calls her pimp from the station. The team follows her to a house where they see one of the pimps, Anthony Samuels, wearing the other earring seen on Madeline. Searching the house, Ray finds a bloody mattress and a lock box filled with money, casino chips and driver's licenses, including Deedee's. In the house, the team finds a badly beaten Diane. when they examine her, they find another tattoo covered over by Anthony. This leads the team to believe she used to belong to another pimp, Dmitri Sadesky, a Russian professor at nearby Western Las Vegas University (WLVU). Ray studies the mattress and finds definite matches to the blood of both Madeline and her unborn child. In the meantime, Catherine Willows reviews the security footage from the Tangiers to determine what really happened to Deedee. Catherine discovers that Diane is the murderer; Diane was jealous that Anthony preferred Deedee to her. Dmitri is caught with evidence in his car from the leg Ray and Horatio Caine found in Miami, and more dead women's bodies are found in the desert. With no other choice, Dmitri helps the team take down the human trafficking ring and admits he did have Madeline, but let her go because she was useless to him. Ray receives messages from Mac and Horatio; both have made crackdowns on the trafficking ring. Ray finds a way to send Madeline a text message saying her mother loves her in spite of everything that has happened. The message reaches Madeline, and she meets Ray outside the crime lab.
