A man who works at a half-way house is found dead in an area filled with drug addicts and prostitutes at night. His belongings were stolen, from car to shoes. Another body is found wearing only his boxers, with signs of a clown's make-up.

When a Hummer in the wrong way runs over an old Fiero, Grissom meets Capt. Brass to investigate the scene. He learns that the Hummer's driver has fled and the Fiero's driver is alive in the hospital. At a car convention, when the host Mr. Daluca opens the curtains to show the latest RV model to the audience, there is a dead woman. Warrick and Det. Louis Vartann learn that the victim is the twenty-nine-year-old model Lisa Schumacher. Dr. Robbins tells Catherine that Lisa was asphyxiated and she had sex before her death. Daluca becomes their prime suspect. Meanwhile, the model Gwen that is working at the convention, goes to the house of her personal trainer Paul Charles to workout and sees him dead through the window. Greg and Sara investigate the crime scene while Dr. Robbins carries out the autopsy. When he sees a black substance in his eye, Hazmat takes Sara and Greg to the decontamination shower. When the body of a boy is found on a bus stop bench covered by a blanket in front of a laundromat, Nick investigates the case. Dr. Robbins tells Nick that the cause of death was asphyxia from heat damage. They identify the victim is Chase Ryan and Nick tries to understand what might have happened to the boy.

The parents of a missing girl are found murdered in a seedy motel room, and a registered sex offender now working as a church pastor is suspected. Meanwhile, Sara tackles a case involving a dead homeless man.