Prince was knocking around with Revolution guitarist Wendy Melvoin when they decided to stop by to see a Bangles concert on Oct. 20, 1986 at the Palace in Hollywood.

The Bangles' version of his not-quite-secretly written "Manic Monday" had peaked at No. 2 earlier in the year, kept out of the top spot by Prince's smash hit "Kiss." Their surprise performance together at the Palace served to complete an unlikely circle.

The lead single from the Bangles' sophomore release Different Light, "Manic Monday" had given the group their first chart hit. This jangly ode to 9-to-5 blues was billed as having been composed by "Christopher," but the author's true identity was quickly revealed. "Prince wrote the album's first single, 'Manic Monday,'" Billboard reported on Dec. 28, 1985.

His early piano-forward demo, later released on 2019's Originals, was spacious and baroque – and maybe a bit too much like Prince to translate into someone else's catalog. He initially planned to give "Manic Monday" to Apollonia 6 back in 1984, but shelved it instead. The song remained there until he stumbled upon the Bangles.

Vocalist Susanna Hoffs says she'd only just discovered Prince when he appeared in their lives. "Soon after I heard ["When Doves Cry"] — maybe even within the same week — somebody let me know that Prince had discovered the Bangles," she told NPR in 2019. "So, it was this sort of interesting feeling of kismet."

Watch Prince's 'Manic Monday' Video

Turns out they had an instant connection: "We were working with Peggy and David Leonard, a husband-and-wife engineer team who had done a lot of stuff with Prince in Minneapolis, and then I guess everybody came west, and they were working in studios in L.A.," Hoffs told the A.V. Club in 2011. "I think Peggy was working with us at the time, and David was working with Prince? Anyway, somehow word got to me to go to Sunset Sound and pick up the cassette from Prince."

The tape included original take on "Manic Monday," paired with another unreleased Prince track called "Jealous Girl." Hoffs said the group immediately knew which of them could be shaped into a Bangles single.

"The title was really great. It just reminded me of 'Manic Depression,' the [Jimi] Hendrix song, and had kind of a psychedelic thing," she told the A.V. Club. "And then it had these great harmonies, and I don't know, there were a lot of things about it where I just thought, 'This is a really good fit for the Bangles.'"

Still, there was more work to be done, Bangles guitarist Vicki Peterson added. Their goal, she says in 2000's Billboard Book of Number Two Singles, "was a Banglefication of a Prince arrangement. He had a demo that was very specifically him. It was a good song, but we didn't record it like 'This is our first hit single! Oh my God! I can feel it in my veins!' We just did the song, and the album, and then sat back and thought about it."

They ultimately decided to unclutter things a bit, and to change some chords. Hoffs told NPR: "That's one thing that we Bangles decided en masse, and were very unified in this, that we wanted to kind of make it ours."

The only question was how the famously fastidious Prince would react. Hoffs told Songfacts in 2012 that he stopped by after the sessions were complete, "and he was really thrilled with how it came out. I think he might have said something like, 'Oh, I was surprised you guys didn't use my track,' or something. But he was very happy with it."

Listen to the Bangles Perform 'Manic Monday' With Prince

They didn't see him again until Prince was somehow on stage with the group in Hollywood.

Bangles manager Mike Gormley said Prince asked if he and Melvoin could sit in for a once-in-a-lifetime rendition of "Manic Monday," but after "Peterson spotted Prince in the wings when the band was playing 'Hero Takes a Fall,' she rushed him out on stage in time to play the song's guitar solo," the Los Angeles Times reported a few days later. "Prince then handed his guitar to Wendy, who played it on 'Manic Monday,' with Prince sticking to the tambourine."

Hoffs told NPR that the whole experience "was just kind of magical. To have this artist who is so brilliant decide that he wanted to come see the Bangles play, and jump on stage and perform with us? It was like the prince had come to the ball and asked us to dance with him, you know what I mean? There was a fairy tale aspect to it."

They all retired to a nearby studio for a little post-show jam, then Prince vanished again – this time, forever.

"He knew all our songs," Hoffs later told Rolling Stone. "We sat until three in the morning just playing Bangles songs – and then he disappeared again, off into the sunset, and we haven't heard from him since."

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