Walter's former bunkmate at the mental institute is linked to the abduction of a young musical prodigy by a serial kidnapper. Peter is concerned when Walter insists on going back to the mental institute to solve the case.
Benson and Stabler are called to a dry cleaners' when a girl's body is found in one of the store's machines, and the detectives soon identify a potential suspect when they discover the victim was involved in an environmental group.
Benson struggles with the responsibility of looking after Calvin, and receives a surprise late-night visit from undercover FBI agent Dana Lewis, who reveals she has been raped and asks the detective to investigate.
A woman claims that a car was stolen with her baby inside, but when her story starts to fall apart, the detectives try to find out what really happened to the infant.
Danny promises a child that he'll open a cold case, the death of his firefighter father. Meanwhile, Jamie saves a baby from a burning building but worries that his new found fame as a hero in the press jeopardises his job.