The third part of the CSI crossover:
Langston is still on the search for Madeline Briggs. A local weather girl, Deedee, is found dead outside of the Tangiers Hotel & Casino, dressed as a hooker. When the team processes her, they find blood from Madeline on the earring Deedee was wearing along with a relatively recent tattoo. They posit that Deedee and Madeline were probably living in the same place and had the same pimp. The team goes to a nightclub and spots a hooker, Diane, with that same tattoo as Deedee. They bring her in on a bogus charge only to get a lead when the hooker calls her pimp from the station. They follow Diane to a house where they see one of the pimps, Anthony Samuels, wearing the other earring seen on Madeline Briggs. Searching the house, Langston finds a bloody mattress as well as a lock box filled with money, casino chips and driver's licenses, including Deedee's. They find Diane, beaten, in the house and she divulges that she had another tattoo that was covered over by Anthony, leading the team to believe that she used to belong to another pimp - a Russian, Dmitri Sadesky, who's actually a professor at WLVU. Langston processes the mattress and finds positive matches to the blood of both Madeline Briggs and her fetus. Meanwhile, Catherine goes through the security footage from the Tangiers to try and figure out what happened to Deedee and discovers that Diane was the one who actually killed her; jealous of the fact that Anthony liked Deedee more than her. Dmitri is caught with evidence in his car from the leg that was found in Miami by Horatio and Langston and they discover more dead women's bodies buried in the desert. Caught, Dmitri helps them bring down the human trafficking ring and admits he had Madeline but then let her go after seeing Madeline was no use to him. Langston finds a way to send her a text message to tell her that her mother loves her no matter what has happened. This message reaches Madeline who picks up the phone to call her mother.