PARK CITY, Utah — “But you’re popular, man!” said Stephen Colbert to LCD Soundsystem front man James Murphy on The Colbert Report in February 2011. Like many others, Colbert couldn’t seem to comprehend Murphy’s recent announcement that he was going to dismantle his band.

This clip helps open Shut Up and Play the Hits, a new documentary that follows Murphy and his bandmates in the days surrounding their last show. The final gig, played to a sold-out crowd at Madison Square Garden last April, capped a six-year run of game-changing dance music that made LCD Soundsystem known as one of the best live bands in the world.

For those in the unlucky majority who missed that final show, directors Dylan Southern and Will Lovelace have granted us a reprieve. Shut Up and Play the Hits — which premiered Sunday night at the Sundance Film Festival here, with Murphy and the filmmakers in attendance — gives us a fly-on-the-wall look at the final hours of a band completely self-conscious of its destiny, yet still on the brink of the unknown.

The film begins when the final LCD show ends. “We just pulled off a high-school play at Madison Square Garden,” says Murphy. The next thing we know it’s the morning after, and we are in his bedroom, where Murphy and his French bulldog are waking up to a new world: One without LCD Soundsystem. The film brilliantly juxtaposes shots of the morning after (and days before) the final show with the concert itself, moving through the set-list and the day after seamlessly, interweaving shots and creating an engaging editorial narrative.

Shut Up and Play the Hits‘ central dialog comes from an interview journalist Chuck Klostermanconducted with Murphy. The questions are fantastic, yielding fantastic answers and a deepened insight into Murphy.

At one point in the interview, Klosterman says he thinks bands are remembered for their successes, but are defined mostly by their biggest failure. When asked what he thinks his biggest failure was, Murphy first skirts around it by saying missing an opening show in Dublin due to a giant ash cloudcaused by a volcano.

“That can’t be your biggest failure,” says Klosterman.

After some serious thought, Murphy says, “Stopping.”

Is Murphy hinting at some level of uneasiness with his choice to move on, or disclosing how he wants to be remembered? It seems he understands that his reason for leaving can’t possibly be as simple as the right decision for his future. Fear comes into play: fear of going for too long, of overstaying his welcome, of not going out on a high note. But ultimately, he says, he knows that breaking up the band is the right move.

As “New York I Love You” plays in the background, shots of Murphy in a cab heading to Brooklyn the night after the show are intersected with balloons falling from the ceiling at the Garden, first floating slowly, then turning into a frenzied mass once they hit the crowd. Sort of like Murphy’s music.

The film differs from other concert documentaries, like Stop Making Sense or The Last Waltz, in that the filmmakers made a concerted effort to document a moment in time by capturing characters in the crowd, they said following the screening. The cameras focus on a couple dancing, and return over and over to a boy, clearly distraught and sobbing at the thought that this will be the last time he will see his favorite band.

If you are a fan of the band, you’ll find the soundtrack amazing. All the music comes from the final performance, and songs like “Dance Yrself Clean,” “All of My Friends,” “North American Scum” and “Someone Great” are all there. Audience members at the movie’s Sundance premiere, which took place at the Egyptian Theater, were clapping and cheering like they were experience a real rock show.

At the end of the midnight screening, Murphy surprised the crowd, composed of many devoted fans, with a short Q&A with the directors. His answers were as fun and as irreverent as expected.

When asked what the hardest song to play during the last show was, Murphy responded: “The ones with the highest register and the latest in the show. It was a long show.”

As for the future of the rest of his talented bandmates, who unsurprisingly don’t make many non-concert appearances in the film, Murphy joked, “To make sure there wasn’t another band as good, I just sort of killed them.”

Age was a theme touched upon frequently in the movie — in the clip with Colbert, the interview with Klosterman and also in Murphy’s normal interactions — so it seemed appropriate that when asked by a longtime fan where he was going next, and where he was taking us with him, Murphy yelled, “I’m going to bed!”

“If it’s a funeral, let’s have the best funeral ever,” says the film’s tagline. They got close, except for no funeral for LCD Soundsystem could really be called “best.”

Something once cherished is now gone.