In 1917, the young, talented music student Lionel (Paul Mescal) meets his fellow student David (Josh O'Connor) at the Boston Conservatory, where a strong bond develops between them due to their great love of folk music. Years later, when Lionel receives a letter from David, it leads to an impromptu trip through the wilderness of Maine to collect folk songs. Their unexpected reunion, the ensuing love affair, and the music they collect and record will have a defining influence on the course of Lionel's life.