Berlin, Germany: A raw documentary about Nirvana frontman Kurt Cobain wowed the audience at its international premiere in Berlin, giving rare insights into the life of a man who, despite or because of his success, felt alienated until his suicide.

Eight years in the making, ‘Cobain: Montage of Heck’ is a 135-minute multimedia roller-coaster ride of unseen home movies, audio recordings, journal entries, drawings and notebook scrawlings, blended with interview excerpts and concert clips.

The Cobain family granted access to ‘everything, with no restrictions’, filmmaker Brett Morgen told the audience on Saturday evening, thanking Cobain's wife Courtney Love, who attended the screening, for her trust and courage.

‘Nobody asked for a single cut, nobody asked for a change, which is essentially unheard of in dealing with such an icon,’ Morgen said. Cobain's heavily distorted brand of guitar music sparked the grunge rock movement of the 1990s, earning him an unwanted label as the voice of Generation X.

The title of the documentary, co-produced by Cobain's daughter Frances Bean, derives from the name of a mix tape Cobain recorded in the late 1980s.

The film shows Super 8 footage of Kurt as a toddler, blowing out candles on a birthday cake and posing with a toy guitar, as a lullaby version of Nirvana's smash hit "Smells Like Teen Spirit" plays in the background.

His parents describe their child as an angel, but also a whirlwind whose activity they tried to control with Ritalin. They speak about their divorce and how Cobain was pushed between different homes as a teenager.

Video scenes show Cobain as a sullen youth, with his own voiceover describing how discovering marijuana and punk music helped him cope with a profound feeling of isolation.

Blowing the myth

The second half of the film gives an intimate peek into Cobain's life with Love.

There is Cobain on a bed, singing the Beatles song ‘And I Love Her’ which was written by Paul McCartney. ‘And that kind of blows the myth, I mean, you would think Cobain would have done a Lennon song,’ Morgen said.

Later, Rolling Stone journalist David Fricke is heard asking Cobain about the outtake ‘I Hate Myself and Want to Die’ from his latest album.

‘Either you're being really satirical, or you're going to a real dark place here,’ he says. Cobain's only response is a chilling laugh.

Cobain committed suicide at age 27 in April 1994.