Billie Eilish: The World's A Little Blurry could so easily have been a bland hagiography that told us nothing about the singer-songwriter, her work, her family, or the music business.
That it is not, and is instead a revealing and moving portrait of a young, vulnerable artist in the process of making her first album, is down to the notable skill of the documentary's director.
R.J. Cutler isn't famous like Michael Moore is famous or Louis Theroux is famous or Asif Kapadia is famous. But he is one of the preeminent non-fiction storytellers working in the burgeoning medium of contemporary documentary film. Anyone who has watched The September Issue (2009), about the lead up to the publication of an edition of American Vogue, will know that he is a fine filmmaker.
The September Issue was built around the strained relationship between Vogue editor Anna Wintour and its creative director, Grace Coddington. The upshot was a compelling insight into the sniffy opulence of high-end glossy magazines and the nature of the people who run them.
He has pulled off the same trick with his 2hr 21min Billie Eilish: The World's A Little Blurry.
Once again, he is following the making of a major piece of content and those responsible for bringing it into the world.
This time around it is watching the work-in-progress that becomes Eilish's debut album When We All Fall Asleep, Where Do We Go? We witness its development as a lived experience for the teenage singer-songwriter and her immediate family.
Given that the record company, the artist, her mum and dad, and assorted PRs will have been all over this project like a rash, it was never going to be a fly-on-the-wall exposé, a point about editorial control Eilish makes more than once by knowingly mugging to the camera and thereby making clear she is fully aware of, and complicit with, its presence.
But, such is the trust Cutler must have built with Eilish, Finneas - her older brother and creative collaborator - and their parents Maggie and Patrick, he was still able to produce a film with substance and something to say.
It starts with a brief Billie backstory.
She was born in Los Angeles in 2001 to two professional actors who were also keen musicians. They started their kids' music education almost immediately, as we see in a home movie clip of a proud dad holding baby Billie over a piano keyboard and playing it by gently bouncing her up and down on the keys.
There is archive talent show footage, in which we see a very young Billie singing, Finneas providing harmony, her mum playing the guitar, and her dad on the keyboard. Maybe it is with the benefit of hindsight, but brand Billie appears to have been something Maggie and Patrick had envisaged from day one: a star not so much born as conceived by her parents.
Both children were home-schooled and shown how to write and produce songs. They encouraged them to make music together, which they duly did, with Finneas's bedroom acting as their HQ.
"My family is the reason I'm the way I am" Billie says, over a clip showing her at around two years old sitting on a piano stool next to Finneas as their mother excitedly announces off-camera "your first duet!"
Everything seems pretty laid back and really tense at the same time. The dream has become reality. Billie's career is taking off, record execs are sitting on Finneas's bed as he plays them a backing track while his little sister, sitting cross-legged at the end of the bed, sings while looking at the lyrics on her smartphone.
Nobody says much, but everything you need to know about the music business is captured in that one scene.
The documentary centres on Billie as a 17-year-old, a year into which she packs what would fill two lifetimes for most people.
She never stops: writing, touring, singing, practising, working, working, working on her album with Finneas.
They tour Europe (with mum as a constant chaperone, which leads to some memorable scenes). Billie gets injured, she mentions having Tourette's syndrome; she falls in love.
She tells us how she once dreamt truly, madly, deeply about Justin Bieber, and now guess what? He's facetiming her!
She says she dreamt of owning a matt black Dodge Challenger one day, and guess what? She's got one on the drive!
Billie has everything, everything she could possibly have wished for.
And yet, she is often miserable, frequently lonely, constantly dreads internet trolls, and is clearly under far too much pressure for someone so young.
When you watch this documentary you realise Noel Coward knew a thing or two when he told Mrs Worthington not to put her daughter on the stage.
His advice was based on the daughter being insufficiently gifted, which categorically does not apply to Billie Eilish, who is a generational talent. But, as we know from all the docs that have gone before that chart the careers of brilliant teenage artists, there is a heavy price to pay for a talent that gives pleasure to millions.
Billie comes across as a lovely, caring person, with her own physical and psychological challenges to overcome. She has the courage to share some of her darkest thoughts and fears in her songs, she is an artist wearing her heart and soul on the sleeve of her record.
There is a foreboding sense in this film of we've seen all this before, it is Act One of a three-act story.
You can't help but think of the recently released Britney Spears documentary, she was a talented teenager who had a lot of parental input but whose life and mental health suffered under the pressure of fame and expectation.
Turning a person into a product works for just about everybody except for the artist. It is the epitome of a Faustian pact, with an important exception: it is rarely the teenage prodigy who does the deal.
Billie Eilish: The World's A Little Blurry is a refreshingly candid, intelligent documentary, if a little a long, which leaves you wondering if a life of relentless celebrity and trying to please everybody but yourself is actually a good plan.
You wonder exactly whose dream is coming true?
I found it sad rather than uplifting, but the music is exceptional and so is the woman making it.
Billie Eilish: The World's A Little Blurry is available on Apple TV+
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