Sydney Sweeney Teases the Peekaboo Boxer Trend's Return With Her Own Unreleased Syrn Underwear

Once upon a time, it was her Paris Fashion Week staple.

Sydney Sweeney was spotted in New York City wearing straight-leg jeans and peekaboo Syrn boxer underwear
(Image credit: Getty Images)

Launching the lingerie brand Syrn gave Sydney Sweeney ample opportunity to style underwear-as-outerwear looks. Even so, her first take beyond the confines of Instagram didn't emerge until February 9, nearly two weeks after Syrn's controversial release.

Technically, American Eagle brought Sweeney to New York City, to ring the opening bell at the New York Stock Exchange. But that didn't stop her from plugging an unreleased Syrn select underneath her jeans.

Sweeney swept her baby blue, slightly undone button-down to the side, essentially pulling back the curtain on her high-rise, elasticized underwear. The white, menswear-looking boxers hailed from Syrn's "Comfy" line, one of four "worlds" designed to help lingerie wearers "move between all the different versions of who we are," the founder said in a press release. "Comfy" pieces haven't hit Syrn's shelves yet. (Only the "Seductress" teddies, bras, and thongs dropped last month, followed by a special Valentine's Day "Romantic" collection on Feb. 4.) However, Sweeney's step-and-repeat suggests her monogrammed boxers will soon be shoppable.

Sydney Sweeney was spotted in New York City wearing straight-leg jeans and peekaboo Syrn boxer underwear

Sydney Sweeney's Syrn revived the peekaboo boxers trend of yesteryear.

(Image credit: Getty Images)

Stylist Molly Dickson knew American Eagle jeans were Monday's non-negotiable, so she picked a light-wash pair that hung low enough to reveal Sweeney's undies. They checked all the boxes for 2026's twist on the straight-leg jeans trend: fitted around her thighs, slightly oversize below her knees, and hems that hide her shoes.

This year alone, Amal Clooney, Jennifer Lawrence, and Rihanna already tested the half-flared, half-skinny silhouette, inspired by Spring 2026 shows from Valentino, Loewe, and more. If it wasn't for her lacy white toe boxes, the Euphoria actor's Black Suede Studio pumps might've gone unidentified beneath the sidewalk-grazing ends.

Being a Miu Miu girl means Sweeney is no stranger to peekaboo boxers. After the trend's rise to fame on Spring 2022 runways, she made it mainstream at the luxury house's Paris Fashion Week show in Oct. 2023. Sweeney cool girl-ified her tweed shorts set with similar white boxers, except the waistband boasted Miu Miu's emblem instead.

Sydney Sweeney wore peekaboo boxers to the Miu Miu Spring 2024 show

Back in Oct. 2023, Sweeney and peekaboo boxers were attached at the hip.

(Image credit: Getty Images)

Less than a year later, Sweeney returned to Miuccia Prada's Paris front row in even bolder boxers. This time, the ruched, low-rise waistband peeked out from beneath sequin short shorts. Her underwear offset the business-casual charm of her oversize blazer, alongside a black-and-white crop top.

Sydney Sweeney wore peekaboo underwear at the Miu Miu Fall 2024 show

A year later, Sweeney once again brought peekaboo boxers as her Miu Miu plus-one.

(Image credit: Getty Images)

If anyone can bring back peekaboo lingerie—in a sea of not-so discreet underwear-as-outerwear—it's Sweeney. Now, she's making the once-runway staple her own, one under-$100 pair of boxers at a time.

Shop Peekaboo Boxer Styles Inspired by Sydney Sweeney

Meguire Hennes
Staff Writer, Fashion

Meguire Hennes is the fashion staff writer at Marie Claire, where she breaks down the celebrity looks living rent-free in her head (and yours). Whether a star is walking the red carpet or posing on Instagram, Meguire will tell you who they're wearing and why. When she's not gushing about A-listers from J.Law to Rihanna, Meguire also covers breaking industry news.

Previously, Meguire was the fashion news writer at The Zoe Report. She received a bachelor's degree in fashion studies at Montclair State University, and has freelanced at Bustle, Women's Health, Well+Good, and more. You can find her words across the fashion, beauty, health, and wellness verticals, because her Libra moon wouldn't let her settle on one beat. Follow her on Instagram for BTS moments from her Marie Claire era.