• Rilo Kiley mastermind’s second solo album blurs the line between her two projects.

For fans of Rilo Kiley’s early work, Under the Blacklight was a rude awakening. The sudden switch from heartfelt folk-rock to Fleetwood Mac-esque L.A. glam was like a stomach punch, but it signalled an important turn in songwriter Jenny Lewis. It was her statement of confidence — she felt she could do whatever she wanted, and she pulled it off. The same transition is apparent here on Lewis’s second solo album.

Rabbit Fur Coat, her first solo release, was a folk-country confessional full of diary-worthy songs about heartbreak and personal upheaval. Acid Tongue doesn’t shy away from such subject matter, but musically it expands Lewis’s parameters exponentially. “Pretty Bird” and “Badman’s World” are both Nick Cave-like in their haunting country noir. “Jack Killed Mom” is a classic Lewis-style moment in which she airs her family’s dirty laundry in public. This time it’s done in a taunting sing-song rather than as a heartfelt ballad. The album isn’t totally ballad-free — the acoustic title track is stunning.

Lewis is strong enough on her own, but some guest spots on Acid Tongue are worthy of mention. Johnathan Rice adds his dark baritone to the eight-plus minute “The Next Messiah,” while Zooey Deschanel appears on “Trying My Best to Love You.” By far the most pleasant surprise, though, is the inspired verse that Elvis Costello supplies for “Carpetbaggers,” sounding like he’s once again at the top of his late ’70s game.

The line between Jenny Lewis’s solo releases and Rilo Kiley as creative outputs is becoming increasingly blurred. As long as the releases are of this quality, though, it doesn’t much matter.