When the Detectives of the Special Victims Unit are called to investigate a rape, they find that the victim is a heroin addict. They also find that she was carrying a decomposing finger in her purse. M.E. Warner is able to determine that the finger belonged to a baby. A DNA test proves that the finger is a match to the rape victim, Clarie. She admits that it belonged to her younger sister, Lisa. When Claire's mother, Grace, is seen dumping Lisa's body in a dumpster, the Detectives begin to suspect her of the crime.
This was a very interesting episode. It just goes to show you that people like Grace should not be allowed to have children. She had three children and two of them died in her care, and the only one to remain alive became a drug addict. It was nice to see Fin get attached to a victim. Normally you only see that happen to Benson and Stabler.