The Best Thing That Ever Happened to Me
performed by Gladys Knight & the Pips
(Song)

When an undelivered letter with a missing child's handwriting on it is found, the team is prompted to reopen the case of an eight-year-old girl who disappeared in 1975. The presumed victim is found to be alive, and is reunited with her parents and her best friend. The person responsible for the disappearance of the victim is arrested.