There’s a reason today’s biggest pop stars make a ritual of promising that their next album is the most personal yet. Intimacy is valuable currency when an artist’s identity and image hinge on hired-gun hitmakers, airbrushed photo shoots and carefully curated social-media posts. Yet Sia Furler, the spotlight-averse singer who obscures her face with Cousin-Itt-by-way-of-Vogue wigs during her rare live performances, revels in just how fake the pop machine can be on her new album, This Is Acting.
The record is made up of songs she wrote for the likes of Adele and Rihanna that never made the cut. (One tune, “Bird Set Free,” was actually turned down by both of those artists.) Accordingly, she’s tried to distance herself from the music. In interviews, she admits to having little emotional attachment to many of the songs and says the lyrics are impersonal, written from the perspective of an artist who likely wasn’t even in the room when she came up with them. She considers her real art to be her music videos, which have been watched more than 1.8 billion times and often feature 13-year-old Dance Moms star Maddie Ziegler performing eccentric choreography; writing songs is just what she does to pay the bills.
Divorcing the work from the person behind it has been the modus operandi of the most recent chapter in Sia’s career. After breaking through in 2005 when her heartbreaking ballad “Breathe Me” closed out the series finale of HBO’s Six Feet Under, the now 40-year-old Australian became increasingly uncomfortable with fame and the demands of touring and turned to drugs and alcohol to cope. After plans for a suicidal overdose were interrupted by a chance phone call from a friend in 2010, Sia backed away from her solo career and started writing for other artists.
After spending years crafting soulful folk-pop, she was writing pop songs on steroids, channeling her struggles with addiction and mental illness—in rare interviews, she is open about her bipolar-disorder diagnosis—into empowerment anthems so towering and grand that even calling them anthems fails to capture their scope. In a time when many radio singles are stitched together by teams of songwriters, Sia became a rare one-woman hitmaker, with an absurdly prolific output: legend has it she wrote the vocal parts for Rihanna’s “Diamonds” in 14 minutes; “Titanium,” Sia’s collaboration with French DJ David Guetta, took her about 40.
Sia’s writing success led to another shot at a solo career, but this time she set limits on living in the public eye. She does minimal press and doesn’t like to be photographed. (She once posed for the cover of Billboard with a paper bag over her head.) For the occasional TV performance, she has recruited stars like Lena Dunham and Kristen Wiig to dance about while she sings in the background. (Recently, Ellen DeGeneres had to assure her audience that, yes, it really was Sia disguised in the corner.) The elaborate staging attracted more attention than a Sia gig would have otherwise, but invisibility was never the goal: abstracting herself was. By fulfilling her fans’ appetite for Sia, the blunt-bobbed blonde with the big voice and the reputation for wacky performances, she’s pulled off a rare feat: separating success from celebrity. Sia, the human, survives by hiding in plain sight.
If this is all indeed acting, Sia is quite good at it. Even when she’s singing something typically out of character for her—she promises to “hypnotize the whole room” with her butt on “Sweet Design,” which recalls late-’90s Destiny’s Child—the songs don’t feel any less personal than the ones on her previous album, 2014’s 1000 Forms of Fear. (That record also contained its fair share of rejects: Sia says its two biggest hits, “Chandelier” and “Elastic Heart,” were both originally offered to Katy Perry.) In a literal sense, Sia is also a talented imitator, incorporating other singers’ vocal styles into her writing and, inextricably, her own performances. She captures Shakira’s distinctive warble on the feverish “Move Your Body” and adopts Rihanna’s patois elsewhere.
Despite the album’s rejection premise, none of the songs indicate a lowering of standards. The rejections say less about the quality of Sia’s writing than they do about the songs’ fit for the artists Sia had in mind. The tropical party starter “Cheap Thrills” would have been perfect for Rihanna, but it’s ground the Barbadian singer has covered many times before and wasn’t isn’t interested in revisiting for her new album, Anti. It’s not hard, either, to imagine Adele blowing through “Alive”—Adele actually co-wrote it with Sia before leaving it off her album 25—yet her cool and collected belting, impeccable as it is, wouldn’t be as moving as Sia’s raspy howling. That’s the thing about Sia: you can’t out-Sia her. It’s often the singers whose vocal chops don’t compare (Britney Spears, Carly Rae Jepsen) who avoid Sia karaoke and succeed at making her work their own.
Still, that doesn’t keep Sia from becoming an occasional victim of her own success. She’s been so adept at churning out big, swooping power ballads that some of This Is Acting feels all too familiar. The simple metaphors she often structures songs around (a barrage of bullets, a relationship’s burning flame) start to feel redundant, and the hallmarks of a Sia song (sturdy piano chords, half-mumbled verses, rushing choruses) approach formulaic. Sia herself has credited her success not to the quality of her songwriting but to her curation—she’s constantly writing songs, but only the finest fraction are ever heard by anyone else. An album like this is economical given her output, but it also threatens the supply and demand that’s worked in her favor.
It shouldn’t be a surprise, then, that the album’s best moments are those that push its creator into new territory. Songs like the Kanye West co-production “Reaper,” yet another track intended for Rihanna, liberate her from the tropes of what a “Sia song” typically sounds like. Here, she floats above whirling church organs and a playful bass line, asking Death to come back for her on a day when she’s not having so much fun. And for a moment, you forget it’s all pretend.
This appears in the February 08, 2016 issue of TIME.