Have you ever had your world transformed in the span of a cab ride? It happened twice for the New Jersey-born taxi driver Diane Luckey, who in the 1980s began moonlighting as the larger-than-life nightclub singer Q Lazzarus. Her first serendipitous passenger was the late director Jonathan Demme, who hopped into her back seat during a 1986 blizzard on his way back from finalizing the music video for Steven Van Zandt’s anti-apartheid protest rap “Sun City.” Eavesdropping on his discussion with the song’s producer, Arthur Baker, Luckey asked if she could play him her music. Demme was struck by the singular depth and verve of her voice, and a long-running creative partnership was born: Q Lazzarus’ music—along with her cover of the Talking Heads’ “Heaven”—would feature prominently in four of his films over the next decade.

Demme’s use of Q Lazzarus’ “Goodbye Horses” in the harrowing Buffalo Bill “makeover” scene in 1991’s The Silence of the Lambs lent the spectral synth-pop oddity a lasting cult notoriety; it’s been covered by everyone from MGMT to the Airborne Toxic Event. Yet Luckey never made a dime from its royalties. Labels allegedly balked at the prospect of signing a Black female rock vocalist, and she washed up as a bus driver in Staten Island after her years grinding as a metal singer in London left her with little but a crippling drug habit.

Over 30 years later, Luckey picked up another director who took an interest in her talent. After singing along to Neil Young’s “Heart of Gold” with Luckey during a 2019 cab ride, the documentarian Eva Aridjis, sensing a familiar face and voice, took a chance and asked outright if her driver had heard of a singer named Q Lazzarus. Luckey initially demurred; she had purposely stepped away from the spotlight, pointedly refusing to speak to intrepid music reporters who wanted to meet the person behind her haunting vocals. But just before Aridjis exited the car, she admitted that yes, she was the real Q. Shortly after, Aridjis began work on a documentary about the rise and fall of the enigmatic and elusive would-be rock star.

Aridjis began filming her documentary with the intention of reuniting Q and her backing musicians for a triumphant return (how very Lazarus). But the director’s vision was cut tragically short when Luckey died from sepsis after breaking a leg in 2022. When producers pulled out, Aridjis launched a Kickstarter campaign to see the film through. The resulting documentary, Goodbye Horses: The Many Lives of Q Lazzarus, comes to theaters next month. Ahead of its release, Sacred Bones has put out nearly two dozen remarkably diverse demo recordings Luckey shared with Aridjis with the hope of finally seeing royalties from her music. From spiraling psych rock to headbanging hair metal, these songs showcase Q Lazzarus’ range, rage, and strange, cosmic beauty.

On its face, “Goodbye Horses” shouldn’t stand apart from countless comparable synth-pop songs from the same period: There’s the reliable snap and kick of a drum machine, the familiar oscillating hum of a buzzing bassline, the rubbery plinks of a wobbling keyboard melody. But then there’s Q, who we first hear as a whispery, wordless coo and then as a rich and velvety-smooth vocal. There’s a destabilizing dichotomy in her voice, which is capable of harmonizing with both the squirming synths and the low thrum of the bass. The tension between her featherlight falsetto and the depth at the lower end of her range creates an unshakable sense of unease. Small eccentricities—the growl when she sings, “I see my hopes and dreams lying on the ground,” the pleading yelp when she cries out, “Oh no sir”—further stymie attempts to categorize her chameleonic voice.

The songs included on the film’s soundtrack do little to contain or classify the mysterious vocalist, instead offering expanded parallel universes that trace Luckey’s journey from Pyramid Club crooner to glam-rock frontwoman and back again. On “Heaven,” which Q performed live for Demme’s 1993 AIDS drama Philadelphia (but which was excluded from the film’s official soundtrack), she sings in a textured howl about the afterlife, imagined as a bar where “everyone will leave at exactly the same time.” Then there’s the glittering new wave of “A Fools Life” and the swaggering dub cover of George Gershwin’s “Summertime,” which feel indebted to her years spent pounding the pavement in London. I keep returning to “My Mistake,” a bubbly house track led by the digital sheen of a Korg M1 synthesizer. As she belts out, “You lead me on!,” it’s hard not to imagine an alternate world where Q found the one-off dance floor success of, say, Robin S. or Crystal Waters. Instead, it’s an untold chapter we only get to experience in retrospect, a could-have-been and never-was.

Though the vinyl edition of Goodbye Horses contains only 10 songs, two of which are different versions of its lead single, the CD and streaming versions of the soundtrack include a dozen more demos, all similarly striking in their heartbreaking mix of pop production, disquieting lyrics, and Q’s indelible voice. On the depressingly named “Fathers, Mothers, and Children Are Dying in the Street,” her voice recalls Danzig’s mournful wail, a blues singer who somehow found herself in a different genre but took all of the tortured agony with her. Her voice is the unifying force, even as it contorts into unlikely arrangements: The glam epic “Momma Never Said” opens with a gnarled incantation that could accurately be described as Animal meets Roy Orbison; “Take the Time” layers vocal harmonies until they recall the breeze passing through a windchime; the electro thump of “The Time Is Right (Dare)” uses her voice as percussion, her opening cries of “Beat it!” punctuating its laser-beam synths. You could listen to the extended soundtrack 10 times and walk away with 10 impressions of Q, while the full extent of her creative range remains out of reach.

The titular beasts in “Goodbye Horses,” according to the song’s lyricist and Q’s former bandmate, William Garvey, who died in 2009, refer to the five senses of the Hindu tradition. For Garvey, they represented the possibility of overcoming worldly concerns and the material plane. When she abandoned her musical career in the 1990s, Luckey took her own first step along that path, trading the hunger for fame and fortune for the security of family life with her husband and son. On Goodbye Horses, Q Lazzarus finally takes flight, transcending her muddled legacy and finding her light after death.