The CSIs are pressed into walking the beat on the Strip along with some local officers, and they wind up arresting a motley crew of drug dealers, transvestites, and hookers. Things take a dark turn, however, when they discover the dead body of a John Doe in a car near the Strip. The victim, later identified as Keith Dobson, was killed by a gunshot wound to the head that Hodges believes came from a plastic gun. After interrogating all of the perps arrested that evening and gradually piecing their stories together into a cohesive narrative, the CSIs determine that Keith Dobson was mistaken for Bobby Reed, the son of a District Attorney and up-and-coming drug kingpin. Using forensic and physical evidence, the CSIs determine that the gun used to kill Dobson was made using a high-end 3D printer. They trace that printer to Rolan Zinn, a local drug kingpin who controls the entire Strip. Reed encroached on the Zinn's turf, so Zinn put out a hit on Reed, hiring a man named Anthony Pak to do the deed. Using Reed and a prostitute he was with as bait, the CSIs trick Pak into making another attempt on Reed's life, and then arrest him before he can do any more damage. This case makes a personal mark on Brass, who discovers that the prostitute they arrested crossed paths with his daughter, Ellie, at some point in the last few months. Ellie sold the prostitute her ring, which Brass actually bought for her mother. We get every indication that Brass' daughter is currently alive and working in Vegas as a prostitute.