The Lonely Child is a song written in the Vilna Ghetto, describing a girl in hiding. It is still performed over 70 years later—long after its lyricist, composer and subjects have passed on.

The song has taken on a life of its own. Who is keeping it alive and why? And how did they find it in the first place? The daughter and granddaughter of the song’s subjectswho for years has struggled with the legacy of the Holocaust in her family—goes on a quest to meet some of these people, to find out what the song means to them.