S6, E22: The head, arm and leg of a woman are found in an abandoned car. With no hands, they can't check for prints, so the only way they can figure out who she is by tracing her artificial knee to the manufacturer. The victim is Mannette Combs; she had been in Iraq and injured her knee, then became addicted to Vicodin, then heroin, and was estranged from her family. Her boyfriend Leon Shragewitz (Glenn Kessler), a butcher, was apparently seen screaming at her. The Medical Examiner found semen in her throat, and Stabler (Christopher Meloni) and Benson (Mariska Hargitay) suspect he caught her prostituting herself for drugs and went nuts. They find Leon and he is hysterical; he admits to killing her by pushing her down the stairs at a subway station after they had an argument. As a result, she broke her neck and died. He left the body there, and as the cops start to track it, they discover her coffin was filled with five twenty-five pound sand bags.