When in New York …

Selena Gomez looked every inch the modern-day Audrey Hepburn at Taylor Swift and Travis Kelce’s wedding rehearsal dinner at MSG Thursday, clad a custom Oscar de la Renta LBD.

The “Only Murders in the Building” star’s stylist, Erin Walsh, shared photos of Gomez’s full outfit on Instagram Friday, including an almost full-length shot of her strapless black lace dress adorned with feminine floral appliqués.

Featuring a thigh-high slit and nude under-layer for a sheer illusion, the gown was styled with Jimmy Choo shoes and $40,000 worth of Fernando Jorge diamonds, including delicate drop earrings and a matching pear-cut ring.

Hairdresser Renato Campora swept the actress’ dark locks into a “Breakfast at Tiffany’s”-style chignon, and makeup artist Soo Park created her equally elegant cat eye and soft pink lip.

Her glam appears to have incorporated unreleased products from Gomez’s Rare Beauty brand, which the A-lister teased on her own Instagram Thursday while giving fans a peek at her outfit.

“SEL in the city,” Walsh captioned her post.

Oscar de la Renta is a fitting pick for the “Who Says” singer, who’s serving as one of Swift’s bridesmaids; as part of Gomez’s bridal party last year, the 14-time Grammy winner wore a look from the very same fashion house.

The latest on Taylor Swift and Travis Kelce’s wedding

Swift paired her tan sequined cocktail dress with Le Vian jewels, including a necklace set with nude diamonds and finished with a pair of opal pendants.

Both she and Gomez have worn Oscar de la Renta’s romantic, intricately embellished designs on a number of red carpets in the past as well.

And with the brand’s former co-creative directors, Laura Kim and Fernando Garcia, highly favored to dress the “Opalite” singer on her big day, Gomez’s rehearsal-dinner look might well be a very stylish Easter egg.