Today, 'Hallelujah' is one of the most-performed rock songs in history. It has become a staple of movies and television shows. It has been covered by hundreds of artists, including Bob Dylan, U2, Justin Timberlake, and k.d. lang, and it is played every year at countless events - both sacred and secular - around the world.

Yet when music legend Leonard Cohen first wrote and recorded 'Hallelujah', it was for an album rejected by his longtime record label. Ten years later, charismatic newcomer Jeff Buckley reimagined the song for his debut album, Grace. Three years later, Buckley would be dead, his album largely unknown, and 'Hallelujah' still unreleased as a single.

After two commercially disappointing outings, how did one obscure song become a global anthem for human triumph and tragedy, a song each successive generation has claimed as its own?