The main character in Pink Floyd's early classic "See Emily Play" is certainly intriguing: She borrows other people’s dreams while crying after dark, putting on a long gown and floating on a river "forever and ever." Her mystery is captured in a whimsical snapshot of the LSD era.

But who was Emily? Many have speculated since the track’s release on June 16, 1967. The most widely accepted — yet technically unconfirmed — answer is Emily Young. A future sculptor, she reportedly met Pink Floyd’s Syd Barrett in 1965 at the London Free School when she was only 15.

"I used to go there because there were a lot of Beat philosophers and poets around," Young told the Independent in 2013. "There were fundraising concerts with the Pink Floyd Sound, as they were then called. I was more keen on poets than rockers. I was educating myself; I was a seeker. I wanted to meet everyone and take every drug."

Describing the famously mercurial Barrett, Young added: "He was absolutely delicious. He was a natural poet and artist, a creature of the forest, like Puck in A Midsummer Night's Dream. He was going through hell at the time because he was taking far too much acid, and he knew he was in danger."

Whoever Emily is — if she ever even existed — the character inspired one of Pink Floyd’s definitive Barrett-era songs: "See Emily Play" remains a densely layered psych-pop anthem with a winding vocal melody, loads of Richard Wright keyboards (Farfisa organ, tack piano, electric harpsichord) and a buzzing slide guitar effect achieved through unclear means. (Legend has it that Barrett used either a ruler or Zippo lighter to create similar sounds onstage.)

Watch Pink Floyd's 'See Emily Play' Video

In its infancy, "See Emily Play" was titled "Games for May," sharing a name with their May 1967 show at London’s Queen Elizabeth Hall. It was an appropriate event to showcase the new piece, as Pink Floyd unveiled a crude — yet incredibly trippy — form of quadrophonic sound. But the band rechristened the track for their stand-alone second single, issued three months after their first, "Arnold Layne."

"We recorded it at Sound Techniques in Chelsea and the song sounded great," drummer Nick Mason told Rock Cellar Magazine in 2020. "The studio engineer, John Wood, was really good so we very quickly loved the sound of it, but the interesting thing was that ... once we'd gone home, [producer Joe Boyd] then went and did that sort of double-speed piano thing in the middle of it. And so, funnily enough, in a way, we were slightly outside having total control of it. I mean, I’ve no complaints about it."

Sadly, this wild studio experiment didn’t make the U.K. edition of Pink Floyd's first album, The Piper at the Gates of Dawn, but the appetizer release still paid dividends: "See Emily Play" became Pink Floyd’s first U.K. Top 10 hit, setting the table for one of rock’s game-changing debuts.

And in the decades since, the song’s wide-eyed mysteries have only grown more fascinating.

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