Who could have predicted that the quintessential girl next door, clad in a simple denim mini and cardi—notice the red, white and blue—would soon take the charts by storm with her blockbuster debut, "...Baby One More Time." (Photo: BritneySpears.com)

Britney quickly cements her reputation as pop Lolita by tricking out a Catholic school uniform into a skin-baring billboard for good girls gone bad. (Photo: BritneySpearsVEVO)

Absolutely. Killing It. Fifteen years before athleisure became a thing, Britney rocked sneakers, kneepads and a neon pleather tube top to kick off her first tour. She was just 18. (Photo: Steve Granitz/WireImage)

The VMAs have always invited excess, but Britney takes it to the next level with a sheer, leopard print, fur accented-top. (Because if not then, when?) (Photo: Kevin Mazur Archive/WireImage)

She's not a school girl anymore! Britney's 2000 MTV VMAs performance shook the world...and this brazen, barely-there, epically ab-tastic getup inspired a generation of viewers to skip breakfast for burpees the next morning. (Photo: Scott Gries/Getty Images)

Brit Brit conjured old Hollywood for the 42nd Grammy Awards in this body-hugging, here-kitty-kitty Randolph Duke number accessorized with an Oscar de la Renta fur stole. (Photo: Steve Granitz/WireImage)

Before there was #twinning, there was Britney and Justin Timberlake, clad in his-and-her matching denim ensembles for their hosting duties as the American Music Awards in 2001. The first and, likely, last time the world has seen anyone rock a zip-up denim gown with a train. (Photo: Jeffrey Mayer/WireImage)

The snake. The tanned abs. The come hither dance moves. The 2001 MTV VMAs proved to be one of Britney's most iconic performances. But has anyone truly given her the mad props she so rightfully earned for the amazing technicolor cape sewn to her daisy dukes? (Photo: Kevin Mazur/WireImage)

It’s hard to know where to rest your eyes—from the leather newsboy cap right down to the lace up stilettos. But Britney’s head-to-toe leather halter dress for the 2002 VMAs was proof that she’d transcended the traditional rules of fashion to slay all day in whatever the hell she wanted. (Photo: KMazur/WireImage)

Britney pays homage to Madonna’s memorable "Like a Virgin" outfit while taking the stage for an iconic (and tongue-wagging) performance with Madge and Christina Aguilera at the 2003 MTV VMAs. (Photo: Chris Polk/FilmMagic)

In one of her tamer (and, interestingly, more timeless) fashion moments, Britney dons a bright pink fur and cargo pocketed bell-bottoms to receive her star on the Hollywood Walk of Fame. (Photo: SGranitz/WireImage)

At the 2004 Billboard Music Awards, Britney accessorized her vintage-inspired black and nude lace cocktail dress with her dog, Bit Bit, and newly-wed husband Kevin Federline, who rocked a matching cream-and-black suit and sneakers. (Photo: Kevin Mazur/WireImage)

Britney kept it covered during Madonna’s Stick and Sweet tour at Dodger Stadium in November of 2008. It takes a certain level of brilliance to dress all school-marm conservative while sharing the stage with Madonna. (Photo: Joe Scarnici/WireImage)

Britney joined "The X Factor" as a judge in 2012, making her flawless debut in a bright pink dress that’s party in the front and business in the back. Nobody does sexy Barbie better. (Photo: Sean Mathis/FilmMagic)

At the iHeartRadio Music Festival in Las Vegas in 2013, guess who was ahead of the curve on bringing back chokers? (Photo: Christopher Polk/Getty Images for Clear Channel)

Brunette-ney in this Michael Cinco Couture dress left everyone at the 2013 Elton John Oscar Party swooning. (Photo: Jamie McCarthy/Getty Images for EJAF)

Britney's skintight nude Mikael D frock with matching heels from the 2014 People's Choice Awards gave us major flashbacks to her iconic 2000 VMAs look, but with a grownup, more mature twist. (Photo: Allen Berezovsky/WireImage)