Bono, the Edge and David Letterman explore Dublin, reflect on U2, go swimming in new doc

After nearly 50 years as a band, unearthing any revelations about U2 is an impractical assignment.

Bono isn’t exactly a reluctant rock star and his brother in all things music, the Edge, is also a willing theorist.

Yet it’s still fascinating to spend 85 minutes with the Irish icons in their hometown – who “go rogue” from bandmates Adam Clayton and Larry Mullen Jr. – and hear them reflect on their history.

“Bono & The Edge: A Sort of Homecoming, with Dave Letterman” – its title a nod to the opening track on the band’s 1984 album, “The Unforgettable Fire” – is part travelogue of Dublin in all of its damp beauty, part cozy sit down with a pair of music wizards and part reminder of how much Letterman and his goofy self-deprecation is missed.

The Disney+ documentary arrives March 17. Here are some insights.

Do Bono and the Edge play U2 songs in the documentary?

The film is framed by an intimate concert at The Ambassador Theatre. Letterman, in true Letterman form, roams around Dublin inviting random people to attend the show with Bono and the Edge backed by a cellist, music students from Mount Temple Comprehensive School and lauded Irish musician Glen Hansard (of “Once” and The Swell Season fame).

The duo performs several classic U2 songs as reinterpreted on their “Songs of Surrender” album, arriving March 17.

Bono, sporting fingerless black gloves and round tinted glasses, stalks the small circular flooring of the venue’s rotunda during “Vertigo,” leading the audience in a percussive clap-along as the Edge wallops on his acoustic guitar. They tiptoe through “Bad,” the first song they ever wrote about Dublin, Bono shares. On "Beautiful Day," the cellist adds sumptuous texture to the reworked version.

Bono shares the backstory of U2’s meaningful 2002 Super Bowl show

Those who remember the band’s magical performance about five months after the horror of Sept. 11, 2001, undoubtedly recall their beautiful, chilling decision to scroll the names of those who died in the World Trade Center attacks and aboard the four tragic flights during “Where the Streets Have No Name.”

Bono said he knew it was “a fragile moment” in American consciousness and wanted to immortalize the moment.

“Super Bowl halftime shows are about spectacle, but the greatest spectacle is one of emotion,” he said.

Footage from the performance includes the tear-inducing sight of Bono opening his jacket at the end of the song to display part of the American flag sewed into its lining.

Bono says his activism causes ‘tension’ in U2

For decades, Bono has immersed himself in causes from spotlighting global poverty to combatting HIV/AIDS, often with bipartisan political support. But his bandmates, while encouraging of his intents, sometimes cringe at the hands he has to shake to accomplish his missions, such as working with former Republican Sen. Jesse Helms in the early 2000s on Third World debt issues.

“Edge said, please, whatever you do, don’t bring Jesse Helms, who personally dismantled the National Endowment for the Arts, to a U2 show. And I … brought him to a U2 show,” Bono admits, as photos of the singer posing with George W. Bush and Pope Francis flash onscreen. “A lot of tension was created by that. I do know that I test their patience.”

Why did Bono and the Edge want David Letterman in the documentary?

At a Los Angeles screening earlier this week for “A Sort of Homecoming,” the primary players, as well as director Morgan Neville ("20 Feet from Stardom"), shared why they wanted the iconic former late-night TV host as honorary moderator.

“Well to be honest, the first idea was Jay Leno, but he found our choice of transport really disappointing,” the Edge joked.

Added Bono, “For us, it was great to see our city and our country through (Letterman’s) eyes. Our music is just better with (Dave) around. The music was better itself just by him being in the room and taking the piss out of us.”

Letterman, who made his inaugural trip to Dublin for the documentary, was equally charmed by his musical hosts.

“I’ve been in television and this sort of thing since I was 18 and at this stage of my life, to have been a part of this,” Letterman said. This screening "is the first time I’ve seen (the documentary) and it’s just a gift. What a lovely piece of work.”

How David Letterman became the 'Forty Foot Man'

Sitting with Bono and Letterman in Marsh’s Library, the Edge pulls out his phone – where he says he has 6,000 voice notes of song ideas – and plays along with a recorded guitar riff. As he builds the song’s melody, Bono tosses out lyrics – impromptu – about Letterman’s visit to the Forty Foot, a famed swimming area in the Dublin suburb of Sandycove.

At the end of the documentary, a finished version of what began as a fun throwaway plays as Letterman returns to the Forty Foot to conquer the mighty waters.

Neville disclosed at the LA screening that Letterman returned to Dublin to film the sequence after the December shoot wrapped.

“Dave called and said, ‘I think I need to jump in the water'," Neville said. “So Dave flew out for a day to jump in the water.”

U2 on the move

• New versions, new lyrics: The best of U2's 40 rerecorded tracks on 'Songs of Surrender'

• U2 heading to Vegas: Band will open the MSG Sphere sans Larry Mullen Jr. 

• Bono surrenders: Mortality, Sinatra and 'ugly pop songs' tackled in memoir

• A message for Ukraine: Bono and the Edge perform in Kyiv subway station

• Bono book tour: Songs, stories and stars fill New York event

This article originally appeared on USA TODAY: Bono, the Edge, David Letterman hit Dublin in Disney documentary