CANNES, France— The most often-repeated thing said about the Velvet Underground is Brian Eno's quip that the band didn't sell many records, but everyone who bought one started a band. 

You won't hear that line in Todd Haynes' documentary "The Velvet Underground," nor will you see a montage of famous faces talking about their vast influence. You won't even really hear a fairly full Velvet Underground track until nearly an hour into the two-hour film. 

Instead, Haynes, the reliably unconventional filmmaker of "Carol," "I'm Not There" and "Far From Heaven," rejects a traditional treatment of the Velvets, a fitting approach considering the uncompromising, pioneering subject. His movie, which premiered this week at the Cannes Film Festival, is, like the Velvets, boldly artful, boundless and stimulating. You sense that even Lou Reed would be pleased by how "The Velvet Underground" refuses the obvious. 

"I didn't need to make a movie to tell you how great the band is," Haynes said in an interview. "There were a lot of things I was going to be like: OK, we know this. Let's get right to how this happened, this music, where these people came from and how this miracle of this group of people came together."

"The Velvet Underground," which Apple will release in theaters and on its streaming platform Oct. 15, plums little-seen footage and features a host of rare interviews, including founding member John Cale (who describes the band as striving for "how to be elegant and how to be brutal"), Jonathan Richman of the Modern Lovers and an early disciple, and Jonas Mekas, the late pioneering filmmaker who filmed the Velvet Underground's first ever live performance in 1964 and to whom the film is dedicated. 

"The Velvet Underground" is most singular in how it resurrects the 1960s downtown New York art scene that birthed and fermented the group. Haynes patiently traces the fertile downtown landscape of Warhol's Factory, the explosion of queer New York and how Lou Reed and the Velvets were turned on by acts like the Ramones or the experimental drone music of La Monte Young. Art, avant-garde film and music collide. The documentary, more than anything, is a revelatory portrait of artistic crosspollination. 

"You really felt that coexistence and the creative inspiration that was being swapped from medium to medium," says Haynes, who notes such localized hotbeds now seem extinct, a victim of a digital world. "I crave that today. I don't know where that is." 

"The Velvet Underground" is Haynes' first documentary. Previously, he's turned to deliberately artificial fictions of great musicians. His "Velvet Goldmine" was a glam-rock fantasia of David Bowie. In "I'm Not There," rather than attempt the impossible task of finding an actor for Bob Dylan, he cast seven.

"When I was doing research on the Bowie of 'Velvet Goldmine' or all the Dylans of 'I'm Not Here,' you come across the real thing," says Haynes. "I always felt like if I'm going to recreate this in a fiction form, I better do something different with it. So you're not comparing it with the real thing, apples to apples. You're in a different language, putting it in a different context and the frame is visible."

Haynes never met Reed, who died in 2013. But he saw him a few times at events like the Whitney Biennial ("I was too scared," he says). And Reed gave his permission to use "Satellite of Love" in "Velvet Goldmine." Laurie Anderson, Reed's widow and a filmmaker, endorsed Haynes directing the film, and other estates, like Andy Warhol's, were supportive. 

Footage by Warhol, the only one to previously really document the Velvets, is laced throughout the film. In split screen, the band members' screen tests for the Factory (usually seen as still photographs) play at length, with Reed or Cale staring provocatively out at you. 

"The only film on them is by one of the greatest artists of the 20th century. That's so rare and weird. There is no traditional coverage of the band playing live. There's just Warhol films," says Haynes. "We just have art within art within art to tell a story about great art."