Thirty-five years ago, young director Albert Magnoli, fresh out of USC film school, unknowingly embarked on a cinematic journey that would change the lives of everyone involved and make concert film history. “We didn’t know we were making a major motion picture,” Magnoli tells Yahoo Entertainment. “And working with Prince wasn’t working with the ‘Prince’ who became the worldwide star he became after the movie. … He was still considered by most people as a fringe artist. So, we went into the film believing we were making a fringe movie.”

But there were some people who seemed to believe that the movie musical Purple Rain, which had a modest budget of only $8 million but ended up grossing more than $80 million at the box office, would be a success: Its star, Prince, and his co-stars, his iconic band at the time, the Revolution.

“He was frantically telling us we were making history: ‘We’re making history tonight, this is history tonight!’” says Revolution drummer Bobby Z., recalling the night they shot their concert scenes — some of the greatest live footage ever caught on film — at the Minneapolis club First Avenue. It was then-19-year-old guitarist Wendy Melvoin’s very first public gig with the Revolution in 1983 (incredibly, three of the recorded performances from that night made it onto the Purple Rain soundtrack album), and she also says she had an idea, even that early on, that her new boss was on to something special.

“Purple Rain, when the idea of the movie came from him, when he talked about doing this, and when a whole bunch of strangers started showing up at our warehouse, we all realized this is not just chat. This is happening,” Melvoin says. “And we were like, whoa. It almost felt... I don't know, it felt scary, and I was ambivalent at first, like, ‘What is happening here, and where is he, and why is he not at rehearsal right now?’ But it felt like it wasn't a mistake. It didn't feel like it was a fool's paradise at all. It really felt like, ‘Oh, this is a sure thing.’"

Bobby, who joined Prince’s musical entourage earlier, in 1979, remembers that even before Prince was an actual rock star, he was already rehearsing, so to the speak, for the Purple Rain rock-star role he was born to play. “For me, when it started, Prince was very unfamous. We were very unfamous together,” he chuckles. “But he still had all these magical qualities. He used to practice being a rock star — like, he couldn’t go into restaurants, or he couldn’t go into a gas station, because he was going to be a rock star and he was going to be famous. He was always projecting himself to be this persona. … It’s just mind-boggling to think that he conjured up all this confidence and skill. We were all mere mortals. I knew that in the first look of the guy, you could tell he wasn’t a human. He was more of a reptile, or something different in his DNA.”

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“One thing that a lot of people don’t realize about him is he lived and breathed what he did,” says bassist Brownmark, who joined the band in 1982. “My first assignment, before I even picked up a guitar, was in Prince’s living room: Look at myself in the mirror eight hours a day. He would tell me how to stand. He said, ‘No, pivot your foot that way. OK, now turn your cheek to do this. Get your shoulder up. Bend your shoulder back.’ That’s how he trained me. Then it got to a point where I would be out at a club somewhere and I’d be standing, I’d have this pose, and people would come up to me and say, ‘Mark, what’s wrong with you? Why are you standing like that?’ I didn’t even know I was doing it.

“He would condition you like that,” continues Brownmark, revealing that the band members even took acting and ballet lessons with Prince, at his insistence, to hone their stage skills for the Purple Rain film. “The more you rehearse, the more you don’t think about it, the less you think about it. Then the more fun you have, and that was the key to the Revolution. We didn’t think about it. He would throw up these cues, and we knew every marker, we knew every cue, and we would hit it — just bam, bam! We knew right where to hit.”

Melvoin admitted she was “terrible” at hitting her marks, but Prince’s direction helped put her at ease. “I mean, it was my first show with the band. The best advice I've ever gotten that I share with other musicians when they're starting, he said to me, ‘When I get nervous, and you hear the beat, and you hear the rhythm, and you hear how fast we're going, cut your body in half time. … It's a meditation. You slow your breathing down, and you don't rush, and you stay behind the beat. And that's where funk lies. And that was the best advice he ever gave me.”

Magnoli recalls being impressed by Prince and his entire band’s professionalism and commitment. “I always felt they had a very strong work ethic and were very disciplined,” he says. “It was just a matter of bringing them from the music world into the film world. In music. you’re working at night and sleeping during the day. In the movie world… you work 14-hour days that start at 6 in the morning. But working with them was a delight. They responded as professionals and never arrived on set late.”

Bobby says Prince had a “grand vision” for the aptly named Revolution inspired by coed bands like Fleetwood Mac, racially mixed acts like Sly & the Family Stone, and the ethnic diversity of Minneapolis’s Uptown neighborhood. “White, black, Puerto Rican, everybody just a-freakin’,” he quips, quoting a line from Prince’s earlier Dirty Mind track “Uptown.” And Melvoin and keyboardist Lisa Coleman especially appreciated the band’s sense of inclusivity. “I was very aware that [Prince] loved female musicians,” Melvoin says. “My being a woman onstage gave him license to be just even that much more androgynous and be more in touch with his own female energy, and I got the permission to be in touch with more of my male energy. … I wanted to be more of a counterpart to him, and he wanted me to be more of a counterpart, so we both got what we wanted out of it.”

Still, Melvoin and Coleman can’t help but roll their eyes when asked about the famous “Is the water warm enough?” intro from the provocative Purple Rain track “Computer Blue.” What did that mean, exactly?

“’Are you gay?’ That’s what it meant,” groans Melvoin, who was actually in a serious romantic relationship with Coleman for 20 years. “‘Do you want to get in the bathtub with me, Lisa? Are we lovers?’ ‘Are they gay, are they not?’ He was working that angle.” Adds Bobby with a shrug, “That was another fantasy episode going on in his brain that he got the public sucked into. Sexually suggestive lyrics were part of his early core to the end.”

Wendy Melvoin, Prince, and Lisa Coleman accept the Oscar for Best Original Song Score for 'Purple Rain.' (Photo: Getty) More

For a while, the multicultural Revolution played in harmony, hitting their commercial and critical peaks with the landmark Purple Rain soundtrack, which came out on June 25, 1984 and went on to become one of the biggest rock albums of all time, claiming the top spot on the Billboard charts for a record-breaking 24 weeks, selling 13 million copies, and winning three Grammys. The Purple Rain movie followed a month later, and eventually won an Oscar for Best Original Song Score (it was the last film to receive the award). But Prince was already moving on creatively, to 1985’s more psychedelic Around the World in a Day and then to the Under the Cherry Moon movie and its accompanying soundtrack, titled Parade, in 1986.

“Obviously, Purple Rain was the pinnacle of his, like, ‘I’m a pop star and these are masterpiece pop songs.’ Afterwards… [Prince] started going in all these different areas, and he was trying to cherry-pick all these different elements of himself to explore,” says Melvoin.

“He prepared for Purple Rain in a way that he never did any other album, because he had to. Because the film slowed him down, and that created time for him to reflect. On most albums, he was done in a second,” Bobby says of the speed with which the restless and prolific Prince usually shifted from project to project. “You know, three weeks, done. But Purple Rain had to stew for about six months, and so he really had to think about it. He could replace tracks. He came up with ‘The Beautiful Ones’ at the last minute. There was things that happened that made it what it is today, and it was forced patience on him.

“Before we even hit the first show of the Purple Rain tour, he was already bored with Purple Rain,” Bobby continues with a laugh. “He really thought that people would be done with Purple Rain — but as we know now, they’re not done with Purple Rain. He was just moving so fast. It was like next, next, next. But Purple Rain is something that people want to examine for centuries now. I look back at everything, but he didn’t — he wasn’t very good at looking back.”

The full, classic Revolution lineup dissolved in 1986 and never played with Prince again, but Melvoin says that after their breakup, there were “years of [Prince] sending smoke signals for us to get back there.” (Fink continued to work with Prince through 1990’s Graffiti Bridge; Brownmark says he was invited to join Prince’s post-Revolution band, the New Power Generation, but declined; Melvoin and Coleman performed with Prince at the Brit Awards in 2006.) But on Sept. 1, 2016, about five months after Prince’s shocking death, the Revolution members reunited for an intensely emotional evening at the club where they’d made history all those years ago, First Avenue.

“It was very difficult for us to climb up those stairs, I’ve got to tell you,” says Bobby Z. “To walk on that stage and play those songs, knowing that he’s not there,” Melvoin says contemplatively, her voice trailing off.

On that night, and the two nights that followed, Melvoin — who handled most of the lead vocals in Prince’s tragic absence — appeared the most emotional, but she says that by the third and final show of the band’s First Avenue residency, “the five of us felt a lift. There were more smiles onstage for us. There was more playfulness, and you could feel — dare I say without sounding too New-Agey? I am not really into this or anything — but you could actually sense that he looked at us and went, ‘It’s OK.’”

“Like kind of a séance,” Bobby adds.

Melvoin nods. “It was weird. And we walked offstage and cried.”

The reunited Revolution now tour regularly, playing songs from Purple Rain and other Prince eras, and while it’s always a bittersweet experience, Brownmark insists, “[Prince] wants us to play. He liked to party, loved to enjoy his music with people. That’s what he wants us to do. Just because he’s gone, he doesn’t want us to go ‘boo-hoo’ and then go away. He wants us to share while we’re here and enjoy what was.”

Additional reporting by Laura Ferreiro.

Read more from Yahoo Entertainment:

· Flashback: 'Purple Rain' director Albert Magnoli reflects on iconic film

· The Revolution reunites at First Avenue: This is what it sounds like when Prince fans cry

· Prince's most memorable onscreen moments

· Prince memoir The Beautiful Ones coming this fall

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