After a young woman has been raped and murdered, her body turns up in an industrial laundry facility. Detectives Benson and Stabler soon find that she was involved in an environmental group called CLEAN, and it isn't long before they track down the prime suspect. However, the case soon puts them in the line of fire and exposes a much larger mystery that includes even more victims. As the investigation progresses, Detective Benson builds a connection to a victim's daughter that invokes her own past in ways she never anticipated.