It's a warm, clear fall afternoon in New York City; R.E.M.'s guitarist, Peter Buck, is shopping in midtown Manhattan, trying to answer the young clerk who is ringing up his Jim Carroll and John Waters paperbacks and keeps asking, "Are you from Boston? Do you know any musicians in Boston?" Unfailingly polite, Buck hems and haws, says that he knows a few Boston musicians and adds that he is himself a musician. But while he might well clear things up by telling her that he's in R.E.M., Buck steadfastly refuses to do so. Of course, if the clerk glanced at the floor, she'd see a stack of local music magazines with Buck and his R.E.M. colleagues — Michael Stipe, Bill Berry and Mike Mills — on the cover.

"I will never tell anyone I'm in this band," says an uncomfortable Buck afterward. "That's not why I got into this. If people ask me, 'Do I know you?' I say, 'Maybe.' I try not to be an asshole about it, but I certainly don't want to be one of those people who goes, 'Yeah, you might have seen my face on the cover of the Dickville Daily Ball, one of the new music papers around today...' I mean, who cares?"

Then he walks a couple of blocks toward Central Park and is soon recognized by two young ladies riding in a horse-drawn cab along the perimeter of the park. "Peter! Peter!" they yell across several lanes of New York City traffic, and Peter Buck grins. "Yeah," he says, "this is a pretty good job I've got."

And how does he see that job? "We're the acceptable edge," he says, shrugging, "of the unacceptable stuff."

And that, in a nutshell, is R.E.M., circa 1987: more popular than ever before, enjoying the spoils of success, having run in territory that's new, yet not completely comfortable with the trappings of fame It wouldn't do for the members of this one-time cult band to embrace mass acceptance too readily, but on the other hand their underground status has all but disappeared — so it would hardly make sense for them to turn their backs on the mainstream.

Besides, it's been a good week. The night before, R.E.M. played the second of two sold-out shows at Radio City Music Hall. Moments before walking onstage, the band had learned that its new album, Document, was in the Top Twenty and the single "The One I Love" had jumped thirteen places to Number Thirty. Since 1982 each new R.E.M. record has outsold its predecessor, but this was an unexpected leap — an album nearing the platinum level and a bona fide hit single for a band whose singles never do well. And as he strolled through New York City, Buck was carrying one of the rewards of success — that afternoon he'd plunked down about $500 for an oddly shaped Italian mandolin-cum-lyre ("a mandolin with pretensions," he says) that he'd liked because of its shape and figured he'd learn to play sooner or later.

Once upon a time it seemed that R.E.M. was the ultimate college band. R.E.M. was formed on a college campus, the University of Georgia in Athens, and its early support came from college radio. Its dense, sometimes obscure, folkish pop-rock songs, with enigmatic lyrics by the group's singer and resident eccentric, Michael Stipe, were perfect fodder for late-night dorm discussions. And its guitar-driven sound, take-it-to-the-clubs approach to touring and low-key image helped shatter the prevailing Anglophilia of the early 1980s and influenced regional bands in college towns across the United States. But now, R.E.M. has finally and fully graduated. The band is out of the underground and into the real world, if you can call rock stardom a real world. And to an observer watching Peter Buck buy a new instrument or get recognized on the street, its hard not to think of the chorus of R.E.M.'s next single "It's the end of the world as we know it," sings Michael Stipe, and then he tosses out the punch line: "And I feel fine."

"I will never, ever, ever, ever play another general admission show, ever. Ever. And I will never, ever, ever play a place that's bigger than the place we played tonight, ever." A pause. "Did I put enough evers in there?" It's one day later, and Peter Buck isn't feeling so fine. R.E.M. has just played to 12,000 fans in Williamsburg, Virginia, the only general-admission show of their 1987 tour — and while nobody was hurt, the crush down front was serious, and the band was upset.

Not that most people could tell. For about ninety-five minutes, the swarthy, genial drummer, Bill Berry, sat in back in an undershirt and white shorts, pounding with real authority, Mike Mills, whose clean-cut Poindexterish looks contrast with the shaggier, grungier look of the rest of the band, played melodic bass lines and sang backup; Peter Buck stood on the side of the stage, cutting a Keith Richards-esque figure with his black jeans and vest, his white shirt and his low-slung guitar; and in the center Michael Stipe staggered about the stage spasmodically, peeling off layer after layer of coats, jackets and T-shirts and charismatically howling out his mostly dark, sardonic lyrics and introducing songs with deadpan, disjointed comments. It wasn't a great R.E.M. show by any means, but it was tough and forceful — and its problems weren't apparent until the final encore, "The One I Love," when Buck, nailed twice by wet sweat socks thrown from the audience, threw down his guitar and stormed offstage.