Early on in Davis Guggenheim’s peerless rock documentary, From The Sky Down, U2’s lead singer Bono talks about his lyric-writing process, inadvertently giving the movie its evocative name. Much like Wordsworth used to do, Bono sings sounds, inflections, ghosts of future lyrics, as he works out what the melody is, what shapes it needs to take, to best evoke the soul of the song. “It’s quite odd,” he says, “writing songs like that, from the sky down.”

It’s a typically Bono-esque moment, thoughtfully yet almost off-handedly wrapping a philosophy into a beautifully punchy, haunting phrase that lingers long after the words themselves are gone. It’s like his lyrics, and like the music of U2 at its best: a powerful burst of evocation and passion, an elemental hymn to transcendence.

Guggenheim captures many such moments as he documents how U2 came to the brink of implosion in Berlin in 1991, but instead fought through the darkness to create one of the greatest albums of all time in Achtung Baby. The movie strips bare the landscape of the band as they finished up the Rattle & Hum tour at the Point Depot in Dublin, on New Year’s Eve in 1990, and entered into what would be their most challenging, and ultimately most rewarding period yet. Those were heady times, ripe for a look back from a band best-known for relentlessly moving forward. U2 are a thoughtful group, well-used to analyzing everything that they do. A rehearsal for their headlining Glastonbury performance earlier this year is shown: the band finish a blistering version of The Fly, and then stand in a huddle to listen to the playback, to tear it apart and rebuild again. That scene is the perfect representation of what happened in the Hansa sessions in 1991, and the perfect summation of the band’s entire, multi-decade career. It’s why they were able to carry each other from the darkness into the bright neon, TV-screen lights of Achtung Baby and the Zoo TV tour. It’s why, three decades in, they have just stepped off the biggest rock tour of all time, the 360 tour, in which they played to more people than have ever been played to by a rock group before.

The relentless, unswerving, unflinching pursuit of perfection; the willingness to travel into the darkness in search of truth, and the ability to bring it back to the light.

All artists of every kind need it; not enough have it.

From The Sky Down brilliantly captures U2’s fierce commitment to the song, and shows us those fleeting, almost mystical moments of creation, when the alchemy of the group is in full effect. The documentary reveals the birth of a key track on the album. Guggenheim’s careful camera observes Bono and Edge as the original DAT tape from the session is played back. In the middle of Sick Puppy, which would morph into Mysterious Ways, some haunting chords emerge, built from two bridges that Edge drops into Sick Puppy as an experiment. From those fragments, Young Heart, as it is initially called, will become the world-conquering anthem we now know as One, the first song to fully come together, and the song that likely saved the band. We see those very first tentative steps as the band quickly realizes that magic is at hand. They immediately switch to finessing the chords, adding bass, vocal inflections: the thrill of creation is a beautiful thing.

But the lesson of the documentary is clear: it doesn’t come easy, nor should it.

If you had to sum up From The Sky Down, it would be about the importance of challenging yourself as an artist, and as a person, in order to truly become what you may or may not even know you can be. The band make it clear that they rarely trust anything if it’s too easy; it’s hard-won knowledge from the front lines of being an artist; of being alive. It’s what Yeats called “the fascination with what’s difficult.” Bono tells us at the end: “you have to reject one expression of the band first, before you get to the next expression. And in between, you have nothing. You have to risk it all.”

This takes up the theme put forth by longtime producing partner Flood earlier in the movie: “it’s fraught with danger, because you can fail at any moment. But that’s the beauty of it, if you’re prepared to remove the safety net, and you’re prepared to really expose yourselves, because your pursuit is after the magic moments, those moments of, ‘wow, I would never have imagined.'”

These are the moments all artists chase; and in life, we seek them too. Moments of transformation, of beautiful change, when we realize what our dreams are and how we can make them come true; or when they come true without our even realizing they were our dreams.

When the Rattle & Hum tour was in full flow, and U2 were embracing Americana, absorbing it, letting it take them to new places, Bono could never have known that his greatest achievements in self-expression were just around the corner, wearing Fly shades, shiny leather trousers, and layers of outrageous make-up. Visions can be hard to make real; but sometimes, out there slogging through the trenches, they take flight, usually after the darkest moments of self-doubt, the moment when you contemplate that the dream might always be just that. Hard work begets brilliance; transcendence doesn’t happen in a day.

As it turns out, the documentary, like all the best documentaries, ends up being about more than its nominal subject, which in this case is the hard-fought, hard-won creation of a brilliant piece of music. But From The Sky Down goes far beyond that, transcending the particular, becoming profoundly universal. It’s required viewing for any musician, writer, dancer… any artist of any kind. Its precise, clear-eyed view of the creative process is illuminating, inspiring, and full of truth about art, creativity, and life.