Though the full contents of Prince's vault are unknown, the unreleased music that has surfaced on bootlegs over the years only hint at what's inside. And as fans wait for official news of how, or if, that music will come out, it's almost certain that we'll never hear "Wally."

Susan Rogers, who worked as a sound engineer with Prince from 1983 to 1988 has told the story of the song on several occasions. It was recorded towards the end of 1986, as they were working on what would become Sign 'O' the Times, at Prince's home studio on Galpin Blvd. in Chanhassen, Minn. Prince had just broken up with Susannah Melvoin, the twin sister of Wendy Melvoin of the Revolution.

"I knew that he was in pain," Rogers said in the interview embedded below. "It was pretty easy to tell, but Prince didn't like to admit any weakness. ... It's a genuine emotion that he's feeling, but he doesn't want to advertise broadly to people that he's feeling down."

Rogers noted that Prince was writing mostly dance music at that stage and hadn't let out his emotions in a ballad until that day. "It was so amazing," she added. Comparing the chorus to Stevie Wonder's "It Ain't No Use," Rogers described the track, which begins with Prince speaking to Wally Safford, a background singer and dancer in the Revolution.

"'Wally, where did you get those glasses? Can I try them on, because I'm going to a party tonight and I want to look so clean,'" she recalled him saying, followed by, "'Yeah, my girlfriend just left, so I'm gonna meet somebody new."

Listen to Susan Rogers Talk About 'Wally'

The chorus found him singing, "Oh my la-di-da," which morphed into "Oh, my malady" and "Oh, my melody."

Rogers gave a few more details to the BBC. "It's beautiful, just beautiful. There's a crescendo. The song gets huge. It breaks down. He says, 'I'm not going out any more.' The background vocal arrangements, the expression of it was just gorgeous. Of course he played all the instruments."

But Rogers' elation wouldn't last long. After making a cassette copy for Prince, he told her to erase all 24 tracks. She pleaded with him to wait a day so that he could think it over, but it was to no avail.

She thinks he cut another version of the song, a belief shared by fan wiki Princevault, who estimate that he took another stab a few days later, with horn overdubs from Eric Leeds and Atlanta Bliss. But that cassette, whose whereabouts are unknown, remain the only known evidence of the song's existence.

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