Kalie Shorr's latest release, "Amy" — a vindictive, hard-rocking missive aimed at an old friend who became an ex's new love interest — officially arrived on Friday (Feb. 19), after an acoustic snippet of the song went viral on TikTok.

Among the 2 million people who saw Shorr's "Amy" video was Butch Walker, a legendary singer-songwriter and producer known for working with artists including pop-punk stars Avril Lavigne and Green Day, as well as Taylor Swift. That style of music has long been a major influence for Shorr, who embraced her punk influences more than ever on her highly acclaimed 2019 full-length debut, Open Book.

It's easy to see why Walker would be a bucket-list collaborator for the singer, who says that unfiltered authenticity is the focus of this song and her upcoming batch of new music.

"I certainly never expected that I would get to record the song with Butch Walker," Shorr says. "Anyone who knows me knows that his music (and the music he's produced) has been the soundtrack to my life. And now it still is, just a lot more literally.

"My music has always been honest and unfiltered," she continues. "And it's been so eye-opening, from Open Book to "Amy," to see how being vulnerable about your hurt can lead directly to healing."

Shorr wrote "Amy" with frequent collaborators and close friends Candi Carpenter and John Caldwell. "Sometimes a song that pours out of me is from hurt and sometimes it's from anger. "Amy" is from both," she reflects.

That anger is underscored by rock guitarwork and lines including, "I wish I could find a f--k to give." But Shorr also wears her sense of betrayal on her sleeve, too: The lyrics don't gloss over the sting of a falling-out with someone she used to trust. "You put his name in a song like you had the right / But I had six years and you had six nights," she sings.

"I'd been working on this song idea for two and a half years," Shorr adds. "After we finished it, I randomly decided to put an acoustic version of the song up on TikTok. I didn't realize how many people had been in a similar position and needed a song to let them know they weren't alone in that hurt."

"Amy" is the first track to be released off of a forthcoming EP from Shorr; the full project should arrive later in 2021. More details are expected to be announced soon.

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