S4, E24: When the body of a murdered 14-year-old girl is discovered in a back alley, Detectives Benson (Mariska Hargitay) and Stabler (Christopher Meloni) discover the victim was a missing Pennsylvania teenager believed to have been kidnapped eight months earlier. However, when the detectives uncover a link between their victim and a prominent New York physician who specializes in reproduction therapy as well as dabbling in human cloning, they also stumble across a group home for alleged runaway teenaged girls.