Warning: Mild spoilers for 'Unpregnant' below.

In "Unpregnant," premiering on Thursday, Sept. 10 on HBO Max, the classic road trip genre also serves as a metaphor for two young women challenging the people — and anti-choice laws — trying to take control over their own decision-making, bodies and futures. Meanwhile, their road trip outfits, worn for the majority of the movie, act as way more than travel gear, helping illustrate their self-expression, individuality and relationship dynamics.

Of course, our heroes' hero looks are also incredibly cute, and perhaps what you'd want to wear, whether you're feeling more type-A popular girl, like Brown-bound Veronica (Haley Lu Richardson) or free-spirited individualist, Bailey (Barbie Ferreira). You can thank costume designer Matthew Simonelli, who's past work includes creating the Brooklyn indie-cool looks in "Search Party" and assisting Eric Daman on "Gossip Girl." 

Along with taking inspo from Richardson's and Ferreira's own Instagrams and scouring imagery from teen-targeted brands, he brainstormed another iconic reference point with director Rachel Lee Goldenberg. "Our main inspiration, of course, was "Thelma & Louise,'" says Simonelli, on a call from Budapest, about the 1991 female friendship road trip classic, starring Geena Davis and Susan Sarandon.

Veronica (Haley Lu Richardson) and Bailey (Barbie Ferreira) discuss a test.

Veronica (Haley Lu Richardson) and Bailey (Barbie Ferreira) discuss a test.

But first, in the bathroom of their suburban Missouri high school, Bailey catches her now-estranged childhood best friend (and Klingon conversation partner) Veronica as she just nailed a test she actually wanted to fail. The latter's pastel tissue T-shirt and floral ruffle mini (above) give just a hint of her sexuality, while communicating her carefully-cultivated, popular-meets-every girl appearance. 

"Veronica is constantly thinking about how she's being perceived and how she's being digested by other people," says Simonelli. (Her Insta content is even "strategic" because "colleges look at that stuff," as she tells an incredulous Bailey.) 

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Juxtaposing her former BFF, Bailey wears an eclectic, over-accessorized outfit of a DC Comics tee, athletic-stripe capris and a vintage print button-down, which speaks to Simonelli's and Ferreira's common high school experience. "Barbie and I connected. We were like, 'Oh yeah, we're weird," he says. "So let's make Bailey the polar opposite [of Veronica]." 

But true to the unfiltered loner that she is, Bailey uses her bold colors, layers and aggressive "prints-on-prints" to empower herself: "She's putting her freak flag out there, but she finds power in it," adds Simonelli. Bailey hopes her unexpected taste in fashion — like her purple angora Kangol bucket hat or her trusty furry green backpack — might serve as conversation points to connect with others.

"But because she's so different than the rest of the school, I just don't think it gets her any traction," Simonelli says. "Whereas, 10 years down the road in New York, she'd be a successful and fabulous artist and people would love her." 

Veronica and Bailey en route.

Veronica and Bailey en route.

Fittingly, Bailey's very extra backpack (in comparison to Veronica's hot pink Fjallraven Kanken) is not an obscure Sesame Street creature. It's actually a customized, one-of-a-kind piece from Lower East Side boutique Assembly New York. After spotting the lively piece in a lookbook, Simonelli headed to the shop and talked the associates into selling it to him. 

"I took that bag and I gutted a stuffed animal and stuck some eyes on it," he laughs. "I thought, maybe at some point, if Bailey wanted to use it to talk to Veronica and annoy her in the car trip, she could do that."

Fearful of confiding in her popular squad or her "Jesus-freak parents," as Bailey says, Veronica asks her old friend to drive 15-hours with her to seek an abortion in New Mexico, the closest state that doesn't require parental consent for a minor. Hence, the two must commit to their drive outfits, which intentionally don't look like wardrobe choices that would stay comfy on a varied climate (and terrain) journey — and in a Trans-Am, no less. "I really liked this idea of these clothes starting to imprison our characters a little bit," says Simonelli.

Bailey literally dresses for a road trip in an "Ocean Drive" (get it?) T-shirt from Missguided and Nascar patchwork shorts by ZITS by Nathan Qualley. "'Oh! It's a thematic look!'" says Simonelli, about his delighted reaction to the pairing, which also resonated with Lee Goldenberg. "It just clicked." The director also loved the combo of the bright orange camo socks from Urban Outfitters with the leopard, color-blocked and winged chunky sneakers by Ash (below). 

"[The producers] definitely didn't get [the full look], but Barbie, Rachel and I were like, 'This is it!'" laughs Simonelli. "We strong-armed our way into those outfits."

Shoe twins!

Shoe twins!

Veronica sits shotgun and on the "opposite end of the spectrum" with a continuation of her youthfully virtuous pastels. She's still in her white Spiritual Gangster sweater with a rainbow pattern — that also brings racing car stripes to mind — which she wore to her infuriatingly awkward dinner with perfectly douche-y boyfriend Kevin (Alex MacNicoll and his floppy hair). Along with her rigid but fit-like-a-dream jeans by Lucky Brand, the long-sleeve knit starts to feel confining, especially for a detour trek through the desert after being kinda kidnapped by deceivingly sweet anti-choice zealots. (Simonelli dressed them in "a real Christian artisanal pickle vibe," inspired by his time spent observing the real deal in Louisiana.)

Veronica's also practically accessorized in more pastels: suburban-chic Coach crossbody and chunky sneakers, which also sartorially symbolize the friendship dynamic. "Her Ash shoes are actually the same make and model as Bailey's — just completely opposite," says Simonelli. "I thought that was a beautiful way to connecting these two characters." 

Even though Bailey and Veronica remain in the same outfits throughout the film, tiny but plot-advancing adjustments are made along the way. The former adds fleece, trucker hats and rest stop-procured sunglasses; Veronica rolls up her sleeves and knots her sweatshirt into a crop-top post "Thelma & Louise" car chase, signaling the turning point to come.

'Since U been goooone!'

'Since U been goooone!'

Veronica's "Thelma" moment arrives as the two finally approach Albuquerque riding in Bob (icon Giancarlo Esposito)'s white stretch limo (also with a touch of "Laguna Beach," via a spirited car karaoke rendition of Kelly Clarkson's "Since U Been Gone.") Readying for her hard-won appointment at the abortion clinic, she finds and changes into a discarded, worn-in vintage-looking t-shirt (top). Simonelli rewatched the '91 movie multiple times for research (and fun). He loved how costume designer Elizabeth McBride transformed Geena Davis's Thelma during her self-discovery moment with a biker tee, tucked into faded, high-waisted jeans

"It's her rebel, outlaw moment, which signals this huge change in her. She's wearing jeans and that shirt and there's no going back. She is a changed woman," says Simonelli. "I wanted that to be true for Veronica." 

Interpreting the iconic look, Simonelli commissioned original art of the sun setting behind a skeleton riding a motorcycle. Then he, Lee Goldenberg and Richardson landed on the perfect tagline for the Madeworn T-shirt: "There's no place like hell."

"This is Veronica's big rebel moment, when she wholeheartedly embraces where she's going," continues Simonelli. She confidently asserts control over her promising future, while embracing and revealing her true self — and rediscovering what true friendship means with Bailey, her ride-or-die.

'Unpregnant' premieres on Thursday, Sept. 10 on HBO Max.

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