On September 14, 2004, Britney Spears arrived at Macy's in New York City in a red satin cocktail dress with tiny hearts all over it to attend a party in her honor. She was 22 years old and four days away from her second marriage of the year (her first, an impromptu Vegas hitching with a childhood friend, lasted 55 hours; a judge annulled it, saying Spears "lacked understanding of her actions" at the time). Spears was in New York to launch Curious, her first perfume, which cost $39.95 and smelled like the waiting room of a fancy spa. She beamed for the paparazzi and held a bottle of Curious in her palm, cradling the aquamarine flacon in one hand, as if it were a delicate fruit, and squeezing the tasseled atomizer with the other like a silent-film star primping in her boudoir. "I'm so excited about doing my new fragrance with all of you," she said, while chewing bubble gum. "It smells amazing, and it is in department stores, so I seriously suggest to be sexy and go out and get it. Seriously."

As she walked away from the microphone, Spears did a little shimmy with her shoulders, a hammy movement that seemed like an anxious reflex. She could seriously suggest that people buy her fragrance, but at that very moment, she was struggling to be taken seriously herself. She was trying to launch a perfume business in the middle of a tabloid maelstrom: She'd recently announced her surprise engagement to Kevin Federline, a dancer whom she had only known for a few months. On top of weathering the media fallout from her whirlwind romance, Spears spent the summer in intensive physical therapy following arthroscopic surgery on her knee, which she blew out while filming the video for "Outrageous." She'd had to cancel the entire back half of her 2004 tour for In The Zone, which meant disappearing from the limelight just as "Toxic" hit the top ten in 15 different countries. When she launched Curious, she was barely healed and just starting to take baby steps back into the public eye.

This is all to say that there was a lot riding on her first fragrance, and Spears knew it, even if she popped her gum throughout its unveiling. Elizabeth Arden had sunk a lot of chemical lab hours and market research into perfecting Spears' scent (not to mention the $52 million it paid her for the deal): it was a saccharine meringue with a light glaze of white peaches and a delicate lotus basenote, the kind of sugar-dusted mist that's like catnip to teenage consumers. But celebrity scents are not always a sure thing. Many of them drop into the market with a thud, lasting only a season never to be heard from again (remember J by Jennifer Aniston or Black Star by Avril Lavigne?). So few of them have lasting power — on the skin or in stores.

Fortunately, if there is one thing Britney Spears knows, it is how to make a hit.

In its first year in stores, Curious didn't just kill, it obliterated. It became a phenomenon. It was the top selling fragrance of 2004, netting over $100 million in sales. To put that in perspective, over the course of her 20-year career, Spears has sold 100 million records worldwide. By 2013, one report stated that in five years Elizabeth Arden had sold over 500 million bottles of Curious. That's five times as many units in a quarter of the time.

The most obvious and also true explanation for this is that the perfume was good. I mean actually good. Curious has a strong, milky sillage that isn't too cloying (where most celebrity scents employ a melted-Slurpee level of weaponized sweetness), and it lasts for hours and hours. In 2005, the scent was a finalist in the Women's Luxe category at the Fragrance Foundation Awards (the Oscars of perfume), alongside Dior's Pure Poison, Prada Eau de Parfum, and DKNY's Be Delicious — which cost twice as much if not more. And Curious is still moving units: Walk into any Rite-Aid, and you'll likely find a locked plexiglass cabinet containing a few boxes of the stuff. You can buy it on Amazon right now. Within the industry, the scent is known as a kind of magical unicorn, the sort of breakout commercial and critical hit that most corporate fragrance firms only dream of when they collaborate with a celebrity — because most celebrity scents are bad.

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Britney-caliber stars often aren't even that involved in making their namesake perfumes: their business team sends out a description of what they want (or a "brief") and several fragrance firms compete to win the contract. Sometimes the celebrity won't even smell the formula until it's done. (Two notable exceptions are Sarah Jessica Parker, who has been said to be intimately involved in every step of her scent creation, and Spears, who, according to Ron Rolleston, the EVP of Global Fragrance Marketing at Revlon, made her tastes very clear throughout the process. "We sat down and talked about her likes and dislikes, colors, bottle shapes, favorite scents, and art that she found inspiring," he says. "Britney's love of flowers and a sensuality in scents forms the DNA of many of her fragrances.")

When a scent goes through a big firm — Coty, Parlux, IFF, or Revlon which together rep almost every celebrity scent you've heard of, along with many designer ones — it is designed by a hivemind, and so much gets lost in every moment of translation that the juice that's bottled and sold is but a weak facsimile of the original idea. The tastes of individuals are wild, but the masses are predictable (they like vanilla, peach, and chemical musk), and it is very difficult to make something transcendent when you have about 100 cooks in the kitchen. This is why so many celebrity scents smell like the same kind of playing it safe — they are like pop songs, engineered with the same backbeat.

But Britney Spears is a wild individual, and Curious has a pulse beneath its honeyed, whipped cream, jelly donut exterior. It suctions itself to the wrist and releases its essence throughout the day in gentle sighs, unfolding and changing almost elegantly. If you encountered the scent in a blind smell test, you might think it was one of those puffy, powdery Guerlain concoctions Parisian girls buy as their first signature scent. In other words, it is far better than it needed to be. Spears was (and still is) one of the best-selling pop artists of the century; her first perfume could have been pure gasoline and it would have flown off shelves, at least for a season. The fact that it has remained in production and in stores is not only a testament to Spears' ever-regenerating star power, but to the fact that she really loves fragrance. And she just might know what she's doing.

It's clear Spears adores her own fragrances — she wears them (in real life and her music videos) and often smatters her Instagram with pictures of her favorite bottles and her latest debut. She tweets about the atmospheric smells she loves, like the scent of vanilla candles. Curious, and its blockbuster follow-up Fantasy (a fizzy varnish that smells like fine chocolate mixed with strawberry Pop Rocks) are strong, heady, perfume-lover's perfumes. In 2013, Spears released a breakup anthem called "Perfume" in which she cheekily sang that she hoped her ex's next girlfriend would smell the lingering traces of her scent. It was a song about marking your territory, but also about marketing it: she may have lost her man in "Perfume," but was making a fortune on perfume.

The fact that she still is may make her an anomaly. According to recent reports, celebrity scents are on the decline. Sales of perfumes with famous faces attached peaked in 2011, and have been on the wane ever since. Cosmo reported earlier this year that big fragrance firms have stopped handing out multi-million dollar contracts to celebrities just to slap their names on a bottle, noting a dip as low as 22% in the category's sales. In the era of online retail, consumer tastes have gravitated toward designer or cult indie brands like Le Labo and Byredo, with minimalist bottles made for Instagram. A lot of buying things these days is about broadcasting that you bought them, and celebrity scents — which have always carried with them the whiff of the uncool and overeager, and a slight touch of class anxiety given their drugstore roots — have not fared well in the attention economy. Rihanna, for example, ditched her former fragrance and cosmetic endorsement deals to launch Fenty Beauty with the luxury conglomerate LVMH. This has allowed her to lord over her own mini-empire rather than lending her name to someone else's bottom line, but also to play along with the Instagram hype machine rather than operating independently of it, dependent on drugstore foot traffic.

Still, In this precarious new landscape, Britney Spears' perfume operation has continued to thrive and innovate. Just this fall, she released Prerogative — her 24th perfume — directly into Kohl's and Walmart stores. It also happened to be her first "gender neutral" scent. Though technically all fragrances are unisex (the difference between women's perfume and men's cologne is a myth cooked up to sell bottles! Anyone can wear anything! Don't believe the lies!), Prerogative is far woodier and spicier than any of Spears' other concoctions, relying on an unctuous amber base smothered with tangy fruit, or perhaps zesty Carolina barbecue sauce (I mean this as a compliment). Spears has been promoting the scent with as much zeal as she has all of her past offerings, flipping her ponytail in Instagram videos in a strapless metallic minidress with the hashtag #myprerogative. A few days shy of 37 years old, she is still selling fragrance with as much gusto as when she told the crowds at Macy's to "be sexy" and buy a bottle, 14 years ago. The only difference is, consumers have spent more than $1 billion on her perfumes since then, according to a rep at Revlon. As she launches another Vegas residency (Britney: Domination hits the MGM in February 2019), Spears is proving that she remains one of the hardest working women in pop; what we don't discuss enough is how she has been one of the hardest working women in perfume this whole time, too.

Despite all her success in the fragrance thunderdome, Spears' perfumes have never quite tipped over into high fashion coverage or even Instagram unboxing gushery, except in secret, back-alley conversations between beauty editors and girlfriends. In a New York Times article from 2005, called "The Guilty Pleasures of Smelling Like Vanilla and Peach," several accomplished women in their thirties bravely confessed that they (gasp!) regularly wore Curious, clarifying that they would never wear the perfume all by itself. One woman told the paper she layered the scent with one by Hermès; another said she "routinely mixes hers with more rarefied essences, a practice she likens to wearing, say, a $14.99 Zara shirt with a $900 Dolce & Gabbana skirt." These women justified their love of the perfume by hiding it, folding it into a more expensive scentscape. All the while Britney was trying to tell us what we finally understand in 2018: There is nothing wrong with loving a $14 shirt. The Mississippi native knew her value, and potential, from a very early age — long before there would be any money to her name.

Looking back, this hand-wringing over wearing a pop star's scent seems silly, if not plain snobby: Perfume is the most invisible of designer goods — no one ever really knows what you are wearing. So the hush-hush quality around buying Spears' scents was never about women not wanting to admit to their friends that they wore Curious; it was about not wanting to admit this to themselves. What did it say that their signature scent came in a hot pink bottle embellished with rhinestones, and that you could buy it with your tampons and gum?

Over the years, Spears continued to churn out undeniably interesting offerings. In 2007 she released Midnight Fantasy, a spinoff of her 2005 gourmand bestseller, Fantasy, which landed a coveted four-star review in the New York Times two years later. "If Chanel No. 5 were a Jolly Rancher flavor, this would be it," wrote perfume critic Chandler Burr. "The stuff explodes delightfully off the skin." He also slipped in a line comparing the "neon sweet" to Britney herself, deeming her to be the human equivalent of a synthetic mango. This was right in the middle of Spears' Circus era, the tender, vulnerable years following the buzz-cut seen round the world, and the custody battles, and the painful, public psychiatric evaluation. She was, in 2009, singing about being a side-show, about how the microscope trained on her life from the time she was a child made her feel like nothing more than a petri dish in pigtails; she was defiantly not overhoneyed, not neon dessert made flesh. Midnight Fantasy may be her best perfume, but it hit shelves during her lowest point; nothing about the caramel-toffee aroma of the juice grafts so neatly onto her personal life. By saying that it did, an esteemed critic was glomming onto the easy version of the Britney Spears story: She was not to be taken seriously.

I've owned Midnight Fantasy for years; it's one of five or so celebrity scents that, if you are deep into perfumery, you just go ahead and buy because you have heard through the grapevine that they are secret gems (others include SJP's Lovely, Kate Walsh's Boyfriend, Rihanna's Reb'l Fleur, Kim K's Nuts 4 Nuts cart around the corner.

People look down on scents like this because they are almost too easy a win; smelling like marshmallow fluff feels like cheating, or like pandering, and always like being sixteen. We want to think of ourselves, past that age, as sophisticates, and so we train our noses to despise the doughy and delicious, even though, deep down, there is a small, un-killable part of every human that would like to live inside a Cinnabon franchise at the mall, and needs to follow every faint trail of cake batter to its physical conclusion. There is a reason that Hansel and Gretel is such a persistent mythology: there but for the grace of gumdrops go I. Britney gets it; just listen to the lyrics of "Toxic."

But it's important to refrain from melding Midnight Fantasy and Spears herself, from melting them into a taffy blob of innocence and sweetness: this is the sort of rhetoric that led to her smashing an umbrella through a car window to begin with. Spears is a survivor, above all things — and perfume is a big part of that story. Buoyed by the consistency of her Vegas residencies (arguably the best thing to happen to her, and pretty much any entertainer who takes one on) and her two sons, she fills her Instagram with inspirational quotes and giddy dances and silly struts for her friends in her cavernous house. There's a lightness to her now, some cosmic weight removed. She seems, from the outside at least, to be happy, and she seems especially happy when she is promoting a new perfume.

There was a time, when if someone asked me what I was wearing, and it happened to be a Spears scent, my voice would go low. "It's, um, Midnight Fantasy?" I would whisper, as if I were doing a drug deal on the street. But earlier this year, a man in line behind me for coffee asked, and I felt no compulsion to be coy about it. I told him that it was Britney, and that he could buy it at Duane Reade; he smiled, and looked relieved, mostly, to find out that the scent he wanted to purchase for his girlfriend was something affordable. And then the barista smiled too. "I love that stuff," she said, as if unburdening herself of a long-held secret. "I just love it."