Taylor Swift has released a song that only her most dedicated fans have heard, and she's added Maren Morris to the mix. The country singer-turned-pop superstar dropped "You All Over Me," her first "From the Vault" release from Fearless (Taylor's Version), on Friday (March 26).

It's a song Swift recorded but didn't release with the others from her 2008 sophomore project. Some internet sleuthing finds song lyrics and a recorded version on Vimeo; it's a softly-spoken, repentant love song that harshly rebukes a perhaps-abusive ex-lover that did her wrong.

"Well I lived and I learned / Had you, got burned / Held out, held on / God knows, too long / You wasted my time, lost tears / Swore that I’d get out of here / No amount of freedom gets you clean / I still got you all over me," Swift sings. Mandolin and harmonica accent the melody, while Morris sings harmonies.

"Whether it’s the Disney vault or the TS vault, you know it’s gonna be good," says Morris on Twitter. "My favorite thing that I don’t get to do very often is to slip into someone’s world and just harmonize."

Aaron Dessner of the National -- who also worked with Swift on her two 2020 albums, Folklore and Evermore -- produced "You All Over Me," which country songwriter Scooter Carusoe co-wrote with Swift, who was only 18 years old when her Fearless album originally dropped.

"Love Story" and "You Belong With Me" were two of the big radio hits from that album. In February, Swift dropped the "Taylor's Version" of "Love Story," and announced that the full Taylor's Version of Fearless is due out on April 9.

"One thing I’ve been loving about these From the Vault songs is that they’ve never been heard, so I can experiment, play, and even include some of my favorite artists," Swift tweets. "I’m really excited to have @MarenMorris singing background vocals on this song!!"

Vulture reports that the new Fearless (Taylor's Version) release will feature six previously unreleased songs, meaning more collaborations could be on the way.

Grammy Awards Red Carpet - Country Music's Best From 2021

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