The gospel-flavored "Jack Killed Mom" is about, you guessed it, matricide. And in the title track, a country-pop ballad Dolly Parton could have written if she'd gone to Woodstock, Lewis presents herself as a female adventurer whose ultimate prize is exhaustion.
This drive to try new approaches is a quality Lewis shares with Costello, her onetime admirer (a few years back, he started declaring Lewis his favorite young songwriter) and current occasional collaborator. The alternative rock statesman proves a spirited duet partner on "Carpetbaggers," a Rice composition on "Acid Tongue." The session inspired Costello to make his 35th album, "Momofuku," upon which Lewis and her posse appear.
"On the day we finished my record he booked the studio for about a week and finished what would become 'Momofuku,' " Lewis said. "I was like, 'I'm backing him?' I truly can't believe it. And he's so cool. He's a chiller, that's what we'd say in Southern California."
Chill is a state Lewis favors these days. She kept the sessions for "Acid Tongue" as open as possible, inviting her friends to drop by and join in on the analog equipment at Sound City Studios in Van Nuys, near where she grew up. Each song was left more or less intact after recording -- no fixing on Pro Tools. This approach was a typical switch for the songwriter, away from the slicker "Under the Blacklight" and toward that more grass-roots feel.
She's still proud of "Blacklight," though it divided Rilo Kiley fans. Some questioned the band's motivations in making a more commercial album. At the time, Lewis favored wearing very short skirts or hotpants onstage; one music journalist, Kate Richardson, created a flow chart of Rilo Kiley's decline as it correlated to the rise in Lewis' hemlines.
"Part of her appeal is that she at least used to write these really good, sad, bitter songs that were kinda sharp," said Richardson, who crafted the chart for Idolator.com. "She had a lot of emotion behind her. But she's also really hot, really cute. So girls were projecting and guys thought she was really attractive. As she started owning the sexual part of her image more, I thought that was fine, good for her. But it coincidentally went along with a change in their sound."
Lewis took it in stride. "That's what you get with a record like 'Under the Blacklight,' she said. "I was wearing hot pants and singing about sexuality. Not everyone understood that we were poking fun."
Lewis said she might be ready for a new persona -- another step in her restless evolution. "It doesn't really have to do with that response," she said. "It's just my own back-and-forth with what I do. So I want to wear hot pants, and then I want to wear cargo pants."
She laughed. "Now, that would be really flattering." Some things, perhaps, are best left undiscovered.