It’s strange to imagine now that Stevie Nicks was ever an afterthought. In 1974, she was working as a waitress in Beverly Hills, California, supporting her guitarist boyfriend, Lindsey Buckingham; the duo played together as Buckingham Nicks and had cut an album for Polydor the year before without much success. Fleetwood Mac bandleader Mick Fleetwood wanted to recruit Buckingham as the band’s guitarist, but the two were a package deal, so Stevie was in. As remarkable a band-of-equals as the Mac were, it is Nicks’s husky voice, the witchy detours of her ur-California girl image — and, most crucially, her songs, first “Rhiannon” in 1975 and then “Dreams” two years later — that became the fulcrum of the band’s massive success.

But even as she helped make Fleetwood Mac into one of the biggest bands in the world, Nicks’s full potential was arguably being stifled. As songwriters, Nicks, Buckingham, and Christine McVie fought to place as many songs as they could on each album, keeping tabs on who was getting more attention. And when the group cut Nicks’s “Silver Springs,” a song about her torrid breakup with Buckingham, from Rumours, it was not just a mistake, but an affront to a certain side of Stevie. On “Silver Springs,” a now-coveted B-side, Nicks drew out her familiar, passionate heartbreak into something almost ugly. There was real anger rising in her hoarse cries of “You’ll never get away from the sound of the woman that loves you,” an anger that felt unparalleled in Nicks-penned hits for the band like “Rhiannon” and “Landslide.”

Stevie Nicks’s brand of rock was in line with a new class of female musicians like Linda Ronstadt, Joni Mitchell, and the Wilson sisters in the late ’70s, who were gradually cracking the folkie, hippie image of the female singer-songwriter. The ballads Nicks made with Fleetwood Mac held beauty and power equally. “In Fleetwood Mac I have a persona, I call myself the Spider Woman,” Nicks said in a 1988 interview. “I try to imagine myself putting on the spider mask. I become very subdued and quieter; I don’t move so fast; I’m in a state of suspended animation.” Writing about experiences that could have been rendered harshly — a bitter breakup in many of her songs, an abortion in “Sara” — she chose to be a little more mysterious, a little softer, taking the stage in gauzy dresses and top hats. Rumors suggested that she was a witch. She never dipped into the kind of intense drama we associate with men in ’70s rock and its unsophisticated machismo. That was Buckingham’s job.

That is, until Stevie Nicks went solo with 1981’s Bella Donna. Suddenly, over the hypnotizing, chugging electric guitar riff of “Edge of Seventeen,” she sounded like an entirely different woman. “In the web that is my own, I begin again / Said to my friend, baby, nothin’ else mattered,” she sang with a sangfroid snarl, inspired by the death of John Lennon and her uncle’s recent passing. There’s a resilient fury to her grief on “Edge of Seventeen,” one that takes up serious space.

Nicks’s first two solo albums — Bella Donna and 1983’s The Wild Heart, both newly reissued by Rhino this month — paint a picture of her as an artist, a rock star, fully fleshed out in her own inspiration and muses. There is a passionate energy that animates both; here was Nicks’s voice, her words, her imagination undiluted by the competing egos and obsessive perfectionism of Fleetwood Mac. Fresh off of writing and recording the polarizing 1979 Fleetwood Mac album Tusk, a record which Nicks has said she felt she contributed very little to, she found relief from the contentious procedures of her band in her solo work. “After six, seven years of Fleetwood Mac, where I was really very much taken care of and kept away from people and very literally cloistered ... I had to really change the way I looked at the world,” Nicks said in a 1981 interview about Bella Donna. “I had to get very strong or I wouldn’t have made it through this album.”

It’s a strength you can hear in Nicks’s voice, which gains a new prominence in her solo work. On Fleetwood Mac songs like “Beautiful Child” and “Sara,” recorded just two years earlier, her languid singing was layered with her bandmates’ harmonies or, on the latter, obscured with dreamy reverb; on Bella Donna, her husky hard-rock potential was fully realized on “Stop Draggin’ My Heart Around,” recorded with her friends Tom Petty and the Heartbreakers, and the surprisingly funky unreleased track “Gold and Braid.” On the 1982 performance recordings included on the new reissue, Nicks wilds out in new ways even on older songs like “Sara” and “Rhiannon.” (Classic, subdued Stevie was still to be found on Bella Donna, though — she played against her harder songs by retreating into Fleetwood Mac territory, particularly on softer tracks like the Don Henley duet “Leather and Lace” and the Laurel Canyon–worthy, mystical throwback “Think About It.”)

As the ’80s progressed and rock stars like David Lee Roth and Steve Perry filled the airwaves with grandiose stadium anthems, Stevie Nicks played the same game by adding an ’80s pop sheen to her music on The Wild Heart. On “If Anyone Falls,” “Nothing Ever Changes,” and her Prince-inspired hit “Stand Back,” Nicks punched up her songwriting with synthesizers, shred-heavy guitar solos, and sax — elements that play a tad cheesy now — while roping in help from MOR rock band Toto and Prince himself. While much of The Wild Heart doesn’t hold up as well as Bella Donna or her work in Fleetwood Mac, the Nicks on record is still a welcome, aggressive incarnation of a singer unafraid to take risks and push her musicianship further. Perhaps this is why a video of Stevie Nicks singing an early version of “Wild Heart” on the set of a 1981 Rolling Stone photo shoot, unable to contain herself as she sits in her makeup chair, has over 1.4 million views on YouTube. “They labor over every detail,” Stevie Nicks said of Fleetwood Mac after she first went solo. “I care about the final feeling when you hear it on a car radio or at home on your stereo.” It makes sense, then, that Steve Nicks wrote “Stand Back” after finding Prince’s “Little Red Corvette” booming in her car.

Over the years, Nicks has described Fleetwood Mac as a soap opera, a dramatic series of events that other people watched from afar. Band members conjoined and then rejected each other, all the while fleshing out their feelings in the laborious music they were making together. It’s a marvel, then, that Nicks’s confrontations within the band always played like a slow burn. “Listen carefully to the sound of your loneliness,” she advised coolly on “Dreams.” But cool wouldn’t do for solo Stevie. Both Bella Donna and The Wild Heart play like the realization of a Nicks who was always bubbling under the surface of Fleetwood Mac: louder, harder, and, ultimately, a woman who knew her rightful place in the world.