Just a couple of days ago, Kurt Cobain: Montage of Heck director Brett Morgen revealed that the upcoming documentary will feature a previously unheard, 12-minute, acoustic Kurt Cobain song. Now we get an even greater glimpse into the film with its first trailer. Watch it above.

As promised, Montage of Heck incorporates animation, exclusive interviews, rare photos and home videos, all from the late Nirvana frontman’s archives. When the film airs on HBO on May 4, we’ll also hear several previously unreleased Cobain songs and more. The trailer features a home video of Cobain and former wife Courtney Love in their bathroom, a scene that was particularly moving for Morgen.

“That’s an image of Kurt no one has ever seen before,” Morgen said in an interview. “I’m so thankful that exists because it gives us such a great window into what they were like when the camera isn’t around – because that’s not a camera from MTV that’s shooting them.”

While we’ll have to wait until May to see the documentary in its entirety, some critics and fans got an early look when the film aired at this year’s Sundance Film Festival earlier this year. The premiere brought together Love and her daughter with Cobain, Frances Bean (who is also executive producer on Montage of Heck), who were previously estranged.

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