The musical shape-shifter has made pop, country, hip-hop and psychedelic-flavored albums. On “Plastic Hearts,” she bends the glorious excess of ’80s rock to her whims.

On her 2010 don’t-call-me-Hannah-Montana album “Can’t Be Tamed,” Miley Cyrus covered Poison’s 1988 power ballad “Every Rose Has Its Thorn.”

The rendition is a mess: a “Guitar Hero”-on-medium-difficulty solo, indiscriminate sprays of aural glitter, drums so compressed they sound like lasers. And yet, in such unholy ground, an auspicious seed was planted: Maybe Miley would sound good singing ’80s arena rock.

A decade and many, many stylistic detours later, Cyrus’s seventh album “Plastic Hearts” arrives at the same wise conclusion.

Take one of its highlights: the stomping, wistful, acoustic-guitar-driven ballad “High,” which finds Cyrus sounding — in the very best way — like a hung-over hair-metal frontman suddenly unearthing a tender side.

“Sometimes I stay up all night,” she sings, tapping into a rich vein of melancholy, “because you don’t ever talk to me in my dreams.”

Cyrus loves to embrace new genres, and she rarely announces these aesthetic pivots with subtlety. The Dolly Parton cameo and leather Nudie suit she sported on the cover made it known that “Younger Now” was her country album; the hip-hop influenced “Bangerz” showcased a cypher’s worth of rappers and Cyrus’s infamous grills; the Flaming Lips-assisted psychedelia of “Miley Cyrus & Her Dead Petz” began with the lyric, “Yeah, I smoke pot/Yeah, I like peace.”

And so here comes “Plastic Hearts” with its cover shot by Mick Rock, the photographer known for his portraits of David Bowie, Iggy Pop and the Ramones.

Mulletted and sneering out from her own high-contrast photo, the 28-year-old Cyrus all but screams, “Are you ready to rock?!”

But this is hardly just cosplay. (Though the greats know that rock stardom always involves at least a little cosplay.)

“Plastic Hearts” is not a trendy rebranding of Cyrus so much as a convincing argument that she’s always been something of an old soul.

Aside from her contemporary Dua Lipa, who shares the sleek and fun duet “Prisoner,” the elder guest stars on “Plastic Hearts” comprise an evocative ’80s-rock mood board: Joan Jett, Billy Idol and Stevie Nicks — plus Cyrus’s grizzled wail, which at times sounds like an amalgamation of all three of them.

Cyrus’s voice has always been a unique instrument: husky, a little froggy and — when a song calls for belting, like her great power ballad “Wrecking Ball” — surprisingly brawny.

Even at 14, when she was cast on the Disney Channel series “Hannah Montana,” her voice seemed to carry a pathos beyond her years.

As Cyrus has grown older and more comfortable experimenting with her gender presentation, she has seemed to revel in the inherent, freeing androgyny of her vocals.

The buzzing low-end of “Plastic Hearts” allows her to play around with its guttural depths, and the industrial churn of “Gimme What I Want” provides the song her “Black Mirror” alter ego Ashley O dreamed of singing.