Fleetwood Mac pretty much owned popular music during the last half of the '70s. Album sales in the millions, sold-out tours, hit singles, you name it. They were everywhere.

After scoring mega-success with Rumours in 1977, the band made a dynamic left turn on Tusk, shaking up the formula. As artful as that LP is, sales took a hit, even though the massive tour that followed sold out every place it played.

Fleetwood Mac needed a break from the road, and from each other. It was the perfect time for the members to explore some individual paths.

Mick Fleetwood set out first with The Visitor, and Lindsey Buckingham later had a modest hit with Law and Order. But Stevie Nicks hit the big time with Bella Donna when it was released on July 27, 1981.

"The solo projects the Mac is doing seem to open it up a little more," Nicks told Canadian Blue in 1981. "Everybody's less on edge. That's the theory we've been working on, and it works. It makes everybody happier, and nobody's jealous because everybody's doing their own."

Producer Jimmy Iovine, at the time, was coming off a hit record with Tom Petty. "I said, 'Well, wow, if he's good enough for Tom Petty, he's good enough for me,'" Nick told ABC in 1981.

Along the way, Iovine kept Nicks and her ego in check by telling her "I know that you're really used to being like the midnight cat queen that comes in whenever you feel like it," Nicks recalled. "This is not how we're gonna do this album. First of all, you only have three months, and second, I don't want to waste my time with a cartoon."

Watch Stevie Nicks' 'Edge of Seventeen' Video

The result was a blockbuster. From Bella Donna's opening title track, it's clear Nicks has something to prove on her own, outside Fleetwood Mac's shadow.

Nicks called in some friends: The Eagles' Don Henley and Don Felder lend a hand; so does Petty and most of the Heartbreakers, who contributed to the album's first single, "Stop Draggin' My Heart Around." The Top 3 hit was co-written by Petty and guitarist Mike Campbell, and is the only song on the record Nicks didn't have a hand in writing.

The album's other collaborations were just as striking, particularly "Think About It," co-written with the E. Street Band's Roy Bittan, and "Leather and Lace," a duet with Henley that reached the Top 10. "Edge of Seventeen" became one of Nicks' signature songs, while "After the Glitter Fades," "How Still My Love" and "Outside the Rain" apply new twists to Nicks' trademark vibe and vision.

Nicks assembled a band, which included many of the musicians who played on the album, for a tour. Bittan, Waddy Wachtel, Russ Kunkel and Benmont Tench joined her for a relatively short, 10-date run. By the end of the year, she was back in the studio with Fleetwood Mac working on their next LP, Mirage.

Bella Donna was an important step for Nicks, one that proved she stand outside the confines of her superstar band. "I wanted my whole life ... to do this album," she noted. "I wanted to do a few of my songs that I loved for all the people in the world that I loved."

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There have been more than 40 of these outside projects, which deepen and add to the band's legacy.

Stevie Nicks Talks About Life After Music

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