Rolling Stone has posted a previously unheard Kurt Cobain demo, where the legendary frontman strums and sings along to a haunting melody. The song was taken from the new documentary, Kurt Cobain: Montage of Heck, which hits theaters on April 10. Director Brett Morgan says the track was discovered in Kurt’s storage facility in 2013. Listen to it below, and let us know your thoughts.

“For 20 years, my dad has been like Santa Claus, this mythical figure,” Frances Cobain tells Rolling Stone of the documentary. “People come up to me and say, ‘Your dad’s so cool.’ And I don’t know him. I want to present Kurt the man.”