For 15 years now -- ever since frontman Billie Joe Armstrong clutched that monkey in the "Longview" video -- they've been credited (and sometimes cursed) for bringing power-punk to the mainstream. Thanks to three simple chords and plenty of snotty sneers, they've sold millions of albums, toured the globe more times that they can probably remember, taken on governments and tried to rebuild cities.

And they've done it all with one foot firmly entrenched in the East Bay punk scene that birthed them, stating their allegiance to gutter punks and Gilman Street at every possible chance. It's been both a blessing and a curse, eternally indebted to their past, but inching ever closer to the future. So you can't really blame them for wanting to put the punk out to pasture.

And despite their insistence that their [article id="1610384"]guiding force is still DIY punk[/article], Breakdown seems to be a conscious move away from the genre -- and the limitations inherent within it. On the album, [artist id="988"]Green Day[/artist] get in touch with their inner arena-rockers, packing 70-something minutes with huge, windmilled guitars, thunderous drums, keening synthesizers, trilling strings and even a few lighter-worthy ballads. It's their Live at Budokan.

Only, to hear Green Day tell it, Breakdown wasn't the product of some knee-jerk reaction or some stadium-filling aspirations ... rather, it was the next logical step in their now three-decade journey as a band.

"We just wanted to evolve naturally. There was no decision like, 'This is how we're gonna sound.' But for this it was like, 'Let's keep moving forward and see where the music takes us,' " Armstrong explained. "I love a lot of, like, British invasion. I love, like, the Who and Cheap Trick and the Ramones. And it's like trying to take that power-pop or that pop-punk or whatever you want to call it, and stretching it into places that are further than we've ever gone."

And though it's a record of high ambition and huge scope, Breakdown actually got its start in a much humbler form: a couple of pie charts tacked to the wall of Green Day's East Bay rehearsal space. Anything to get the creative process started.

"After we came back from tour, we started fooling around with ideas, coming into the studio with a blank page sometimes. You don't know what to do," drummer Tre Cool smiled. "So we got some drum heads and we put a nail in the wall, and we wrote sort of a pie graph thing, of different eras and genres on there, and we'd spin it, and it would say like, 'Death Metal, '60s Garage Psychedelic' or whatever, and then we'd be forced to go in and write something with that ... that's how it all started."

And from those beginnings came an album that's already being called a [article id="1610695"]monumental achievement[/article], and a worthy successor to their globe-uniting American Idiot. And for Green Day themselves, it's been a liberating experience. Finally free of the shackles of punk, they're already thinking about their next musical movement ... and dare we say, it might be a happy one?

"I think you can write about joy," Armstrong laughed. "I mean, technically, we were a slacker band back in the day ... we didn't care about anything, but you keep evolving, you know? And I think we're capable of doing anything."