Five years ago, Little Big Town seemed unlikely to become one of the most daring groups in country music.
Its 2005 hit "Boondocks," about taking pride in where you came from, displayed a winning defiance, but the coed quartet's subsequent records turned bland and conventional even as the group perfected its signature four-part vocal harmony. By 2010's "The Reason Why," Little Big Town was basically Lady Antebellum plus one lady -- and minus that trio's gripping prom-night drama.
Then, in 2012, came "Pontoon," a delightfully suggestive ode to "motorboatin'" that earned Little Big Town its first No. 1 on the country chart. Clearly emboldened, the group ventured further for last year's excellent "Pain Killer" album, cranking the guitars and weird textures and singing about lust and obsession with sly intensity.
One tune, the stripped-down ballad "Girl Crush," even sparked a Nashville controversy with lyrics some interpreted as a same-sex fantasy (which of course is what makes the song so great).
Little Big Town emphasized that newfound edge Thursday night at the Greek Theatre, where it performed most of "Pain Killer," including the propulsive "Save Your Sin" and "Tumble and Fall," which evoked the honeyed savagery of late-'70s Fleetwood Mac. For the album's title track, three horn players joined the band, pushing a loping reggae groove closer to mariachi.
Yet in an encouraging development for country music, this kind of risk-taking hasn't diminished Little Big Town's commercial standing. "Girl Crush," despite the reported protestations of conservative radio programmers, went to No. 1. And this week the group was nominated for five Country Music Assn. Awards, more than superstars Miranda Lambert and Kenny Chesney.
So there was a cheerfulness to this show that buoyed even the darkest material, such as the noir-ish "Faster Gun," and that gave party songs like "Day Drinking" an added celebratory charge.
Indeed, the evident good mood led the foursome's members -- whose toothy grins and mix of blond and brown hair call to mind a countrified Abba -- to share the spotlight with two unannounced guests: first a fan whose homemade sign got her onstage for a group selfie, then Tori Kelly, the ascendant pop-soul singer who came out to do her hit "Should've Been Us" with freshly thickened harmonies from her hosts. (This kind of outreach isn't unfamiliar for Little Big Town, which teamed with Ariana Grande for a less effective duet at least year's CMA Awards.)
The energy flagged only when the band reached back for its earlier, more tradition-minded tunes; "Bones" and "Little White Church" were aiming for a rootsy sincerity but just felt dull, especially compared with a vivid opening set of old-fashioned country music by Ashley Monroe.
Country's implicit promise is that you can always go home to the boondocks. But that doesn't mean you should.