In 1972, Rolling Stones front man Mick Jagger lent his vocals to then-rising star Carly Simon's single "You're So Vain."
Upon its release, the song climbed to the top of the charts and helped catapult the singer-songwriter to worldwide fame. It earned her multiple Grammy Award nominations, including Record of the Year, Song of the Year, as well as Best Vocal Performance, and turned her into a household name.
Everyone wanted to know who Simon was singing about, and rumors ran amok about who it could possibly be. Many of her fans had fingers pointed at Jagger, but Simon insisted it wasn't him.
The pair actually remained close for years, and in Simon's 2015 memoir Boys in the Trees, she used the word "electricity" to describe their relationship.
They did drift apart eventually, Simon told Rolling Stone in 2016. She explained that she last saw the rocker at an after-party, but she was "very uncomfortable" during their encounter.
She also shared some more stories about her and Jagger in her book, including a studio session they had in 1972 during which they recorded a song with the lyrics, "Funny, funny, funny, funny, how love can make you cry."
Unfortunately, the track mysteriously vanished after their jam session was interrupted by Paul and Linda McCartney, and it wouldn't resurface for decades.
"I harmonized with him as it became a chorus, an improvisation that was later searched for and never found among the multitracks at AIR Studios," she wrote.
The duo never released any other music together, despite the pressure from their fans. For those who have been lucky enough to still be around, the wait has paid off.
After 46 years, the song has finally been found by a London-based Rolling Stones collector Matt Lee, according to the Associated Press. Apparently, the lyrics are the same as the ones Simon previously mentioned but with just one minor change.
Lee sent the song to Rolling Stone magazine and they promised to pass it on to Simon. Some speculate that the recording has been at Warner Bros. Studios the whole time, but Lee has refused to disclose the song's true hiding spot.
However, he did take to Twitter to tease that the duet is "super great."
Neither Simon nor Jagger's publicists have commented on the new song, which is titled "Fragile."
At this time, there is no guarantee that we'll be hearing the duet anytime soon, but, that's not stopping us from getting excited just thinking about it.