Lili Reinhart Wore Archival Elie Saab Couture at "The Love Hypothesis" Premiere

Lili Reinhart brought pure fairy-tale romance to the New York premiere of "The Love Hypothesis," and she did it with a piece of fashion history. The "Riverdale" alum, who stars as Olive Smith in the Prime Video adaptation of the viral BookTok novel, walked the red carpet on September 17 in a gown that instantly had fashion fans buzzing.

Lili wore an archival dress pulled straight from Elie Saab's Spring/Summer 2004 Couture collection, styled by celebrity stylist Ib Abdel Nasser. The ethereal piece was crafted from soft pink chiffon layered with intricate green vine embroidery and shimmering beadwork throughout the bodice and skirt. A deeply plunging neckline framed her torso, with thin straps flowing into sheer, trailing fabric behind her shoulders. The fitted silhouette wrapped snugly around her hips before opening into a dramatic, dangerously high slit, all finished off with a sweeping train that added serious old-Hollywood drama to the carpet.

Nasser kept accessories minimal, letting the gown's craftsmanship do the talking. Lili wore her blonde hair in loose, effortless waves with a clean center part, and kept her makeup soft, subtle eye definition, flushed cheeks, and a glossy pink lip.

On the carpet, an interviewer asked whether the pink-and-green color combo was an intentional nod to Brittany Murphy's iconic dress in "Uptown Girls." Lili laughed it off, confirming the look was simply an authentic archival Elie Saab piece rather than a planned homage.

The gown fits neatly into Lili's larger strategy for this press tour, she's been leaning into vintage and archival pieces rather than new-season looks throughout promotion, having already referenced "How to Lose a Guy in 10 Days" and "Ever After" with past looks. It's also just the latest in a string of standout style moments for Lili this month, she was recently spotted in New York in a bold Zimmermann aviator jacket and flare jeans, proving her range goes well beyond the red carpet. "The Love Hypothesis," also starring Tom Bateman, hits Prime Video on September 23.