Lady Gaga had a chokehold on the zeitgeist. Justin Bieber owned the Internet. Dr. Luke dominated hit radio; the critics loved Arcade Fire. Eminem was resurgent; Taylor Swift was a juggernaut; Kanye West was everywhere. Yet the pop music story of 2010 might just be Lady Antebellum.

You may not have heard of Lady Antebellum, but you’ve heard them. They’re a group from Nashville who sing slight, pretty songs about falling in love and breaking up. Their 2008 debut album sold 1.6 million copies and generated three big country hits, including the No. 1 single “I Run To You,” a lover’s desperate plaint delivered skillfully, and with no discernable trace of desperation, by the group’s co-lead singers, Charles Kelley and Hillary Scott. (Dave Haywood, a rhythm guitarist/vocalist with the hangdog look of a third-wheel, rounds out the trio.) Lady A used the same formula—lustrous vocal harmonies, minor chords, a vaguely-sketched romantic melodrama—for “Need You Now,” the title track of their second album. The song first hit the radio airwaves in August 2009 and hasn’t stopped playing since.

“Need You Now” is a rarity: a country hit that has leapt across genres, borders, oceans, and, nudged along by the foursquare beats of remix DJs, penetrated the normally country-free sanctum of the discothèque. It spent five weeks at the top of Billboard’s country-singles chart and reached No. 2 on the Hot 100, one spot behind Rihanna’s “Rude Boy.” The song topped the Billboard Adult Contemporary for 10 weeks and shattered the record for the most weekly plays in the 14-year history of Adult Top 40/Adult Pop Songs countdown. It was a No. 1 hit in Mexico, New Zealand, Switzerland, and Brazil and cracked the Top 5 in more than 20 countries, including France, Spain, Portugal, Sweden, Finland, Norway, and Israel.

Meanwhile, the Need You Now album is—in anemic current record-industry terms, at least—a blockbuster. It occupied the top spot on the Country Albums chart for more than half the year, 27 weeks. It has sold 3.6 million copies; only Gaga, Bieber, and Eminem’s albums sold more. Two other singles, “American Honey” and “Our Kind of Love” have gone No. 1 country; the current Lady Antebellum hit, a string-swaddled ballad called “Hello World,” is at No. 14 and climbing.

It’s an impressive feat for a group that strives to be as anonymous as possible. Scott and Kelley are attractive in a blank way that fails to impress itself on your memory: pretty gal with blond mop, tall dude with close-cropped beard. Their voices are likewise blandly serviceable. Kelley’s slightly huffy tenor and Scott’s fluttering soprano serve entirely as a means to an end—to navigate efficiently from verse to chorus to bridge and back again—the principle evidently being that any hint of character or charisma would fatally sabotage a song. The only thing about Lady Antebellum that raises eyebrows is its name, which turns out to be a bait-and-switch. When I first popped their 2006 debut in my CD player, I assumed were like Montgomery Gentry—country good-ol’ boys, belting out burly regional pride anthems with a Confederate flag or two draped over the drum riser. But Lady Antebellum aren’t redneck in the slightest and only nominally country.

In fact, it’s hard to pin them down at all: The group’s defining quality is a kind of nebulous in-betweeness. They’re not quite country, pop, or rock. They’re neither soft nor hard. Their tempos are stubbornly mid-; whether exulting in a “perfect day” or lamenting a doomed romance, the emotional temperature in their songs remains mild to lukewarm. In “Need You Now” they sing, “It’s a quarter after 1/ I’m a little drunk/ And I need you now”—a little drunk, not too. Aesthetically, spiritually, sonically—Lady Antebellum stand for moderation. Medium is the message.

Take “Our Kind of Love,” the No. 1 single released last Memorial Day. It’s a chugging roots-rock anthem about young lovers, “lazy Sunday afternoons,” skipping rocks on riverbanks, “driving on an open highway/ Never knowing what we’re gonna find,” etc. In other words, “Our Kind of Love” is a classic summer single, with catchy verses that crest into a catchier chorus, and a lyric that strings together sub-“Born to Run” clichés. “Always holding hands, never making plans/ Just livin’ in the moment, babe,” sing Kelley and Scott. “Just two kids, baby, always tryin’ to live it up.”

Those devil-may-care sentiments sound funny coming from Lady Antebellum. Tonally, texturally, “Our Kind of Love” is off: It’s hard to imagine a more mild-mannered song about reckless romance. Of course, Kelley, Scott, and Haywood don’t want to sound reckless. Lady Antebellum never strain; they’re not trying to be flashy or rugged and coming up short. They have an aesthetic comfort zone—a comfy zone, you might say, as snug as a goose-down duvet—and they stay happily nestled within it. Their kind of music, like their kind of love, is dull by design.

This sets Lady Antebellum apart. Pop is going through one its periodic extravagant phases, an era of heightened spectacle and raised volume and outsized personalities—flamboyant divas, loudmouthed rappers, teenpop idols who scatter their stardust across multiple media platforms. Even adult contemporary stars are getting more emphatic; this year, Sade and Norah Jones stepped away from the brunch table, serving up songs full of bolstered guitars and hefty beats.

In this environment, Lady Antebellum’s charisma deficit has become an asset—just the thing for listeners who want simple, tuneful songs delivered with a minimum of fuss and no information age distractions. Is it any accident that the group’s megahit, “Need You Now,” was lifted almost note-for-note from “Eye in the Sky,” the 1982 soft-rock smash by one of history’s most anonymous hitmakers, the Alan Parsons Project? Lady A are up for six Grammys, and they’re by far the strangest of the big nominees, the weird wallflowers who’ve party-crashed the prom. Consider their competition for the best-album Grammy: Arcade Fire, Eminem, Lady Gaga, Katy Perry. In 2010, Lady Antebellum are a novelty act: superstars with zero star power.

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