Jennifer Nettles' new solo album is a round peg too big for country music’s square hole. Actually, ‘That Girl’ is sort of a zig-zaggy shaped object that doesn’t fit neatly within any genre’s stingy requirements. Jazz, blues, country, big band, Broadway, classic rock … Nettles dabbles.

Strong songwriting holds down the 12 songs -- but many are sneaky. One has to listen to the opening track ‘Falling’ a few times before realizing it’s a “first time” song as satisfying as ‘Strawberry Wine.’

They circled all around me / Like confetti on fire / They were nothing when compared to the burning in my head,” Nettles sings of her vantage point following an outdoor tryst.

‘Jealousy’ is another example of a track that will make a casual listener stop and stare at their speakers. “I didn’t really mean / To cause such an ugly scene / Showing up at your house, half-drunk and crazy b----, I called you out,” Nettles spits between a funky, lounge act instrumentation that is anything but vindictive. What she’s saying and how she’s saying it don’t match, which make for a very compelling track.

Songs like ‘Moneyball’ may fly over a few heads, but this singer has never been afraid to go after a deeper lyric so most of her Sugarland fans should get it. Sonically, the album flip-flops between soft, organic expressions and feisty, funky orchestrations. At times -- like during ‘Know You Wanna Know’ -- she’s on Broadway. Other times, she’s a Delta queen circa 1965. Her cover of Bob Seger’s ‘Like a Rock’ and her original ‘Good Time to Cry’ are the two vocal standouts. The later is a jazzy performance that will remind fans of ‘Stay’ in terms of its pure vocal strength.

‘Thank You’ and ’This One’s for You’ are two simpler songs, presumably written with husband Justin Miller or son Magnus on her mind. They’re sweet and more accessible than ‘This Angel,’ another ballad that feels ripped from her diary. Variety is what one expects from Jennifer Nettles, and she delivers with ‘That Girl,’ an album that is certain to keep fans leaning in to hear what comes next.

Key Tracks: 'Falling,' 'That Girl,' 'Good Time to Cry'

Listen for Flaws: Nettles recorded 'That Girl' live, and didn't worry about chair squeaks, out of place breathes or other sounds a more nervous singer would smudge out in editing. The song 'This Angel' contains a few of these "mistakes," she says.

Did You Know?: Nettles co-wrote 11 of the 12 songs on 'That Girl,' but had help from famous friends like Richard Marx, Sara Bareilles and Phillip Sweet from Little Big Town ('Thank You').