Amanda Seyfried Stuns at 2021 Oscars in Plunging Red Armani Gown and Old Hollywood-Inspired Glam

Amanda Seyfried arrived at the 93rd annual Academy Awards and brought the high-fashion glamour we expect from movie's biggest night

The first-time Oscar nominee, 35, looked elegant in a custom scarlet Giorgio Armani Privé strapless tulle ball gown. She pulled her hair back into a low bun with classic finger waves, wore a crimson lip and accessorized with Forevermark yellow diamond drop earrings and Stuart Weitzman heels. The whole look appeared to be a nod to Mank, the film for which she's nominated, which takes place in 1930s-era Hollywood.

Seyfried — who's up against Olivia Colman (The Father), Youn Yuh-jung (Minari), Maria Bakalova (Borat Subsequent Moviefilm) and Glenn Close (Hillbilly Elegy) for Best Supporting Actress for her role in Mank — joked during E!'s Oscars pre-show that it was surreal to be out in the world after a year of quarantine. "I really can't believe we're around people right now," she said. "It's like the Twilight Zone. In a good way."

Chris Pizzello/Pool/Shutterstock

Hairstylist Renato Campora twisted Seyfried's hair into a retro, old Hollywood up-do to complement the billowing ballgown.

"I was inspired by Amanda's character Marion Davies in Mank and her beautiful dress for this evening. I wanted a couture style of hair — precise and vintage," he said.

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To create the look, Campora blew out the actress's damp hair using the Dyson Supersonic hair dryer Professional edition, and then used the Dyson Corrale straightener to smooth it out. Then, he created a dramatic side part, brushed the strands into a low ponytail, curled the ends using a 1-inch iron and twisted it into a low-hanging bun at the nape of her neck. He finished by smoothing the top of her hair again with the Dyson Corrale straightener and pinning it down to the rest of the style. A little bit of Wella Stay Essential Hair Spray completed the look for extra shine and hold.

Meanwhile, makeup artist Genevieve Herr used a dark brown eyeshadow and a cranberry shimmer from the Lancôme Hypnôse 5-Color Eyeshadow Palette in Rose Fusion ($50; lancome-usa.com) on the Lancôme Ambassadress' eyes and applied the Lancôme L'Absolu Rouge Drama Ink in Nuit Pourpre (launching in May) on her lips.

"The glorious red tulle of Amanda's Armani gown, with its combination of classic and modern architecture, inspired me to use a bold, complementary color on her lips, while choosing warm colors and bright highlights on her eyes," Herr explained.

The actress has given us plenty of glamorous moments during this year's mostly virtual awards season, including at the Golden Globes in February where she watched the show from home in a custom coral Oscar de la Renta gown. (Which is even more impressive considering she and husband Thomas Sadoski welcomed their second child, a son, in September.)

RELATED: Amanda Seyfried Wants to 'Share' Her Mank Oscars Recognition with Her Dad: He's 'a Lover of Old Movies'

At the time, her stylist, Elizabeth Stewart, told PEOPLE that the dreamy confection almost didn't make it to the actress, who joined the virtual telecast from Savannah, Georgia, when it was being shipped from the label's studio in New York City.

Marcus Mam; Courtesy HFPA

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"The dress was lost for an entire 36 hours on its way to Savannah," Stewart revealed.

Luckily, with some help from the Oscar de la Renta team, they were able to track the dress down. "Someone from Oscar de la Renta drove hours to the 24-hour FedEx hub in Newark, New Jersey and stayed there until they found the dress in the nick of time!" Stewart explained.

Earlier this year, Seyfried (who was also nominated for a Critics Choice Awards for Mank) shared that transforming into the legendary Marion Davies for the film was all about capturing the famed actress's "essence."

RELATED: The 2021 Oscar Nominations: Chadwick Boseman, Andra Day and Carey Mulligan Lead Nominees

In a PEOPLE exclusive clip, Seyfried said she "watched a bunch of her movies and I read her autobiography, which is hilarious and interesting and insightful" in becoming Davies for the Netflix film.

She continued, "It was just such a gift to know that I really understood her in certain levels. We're both actors, we both feel like we were dropped into this dream world."

Lily Collins, Tuppence Middleton, Arliss Howard and Charles Dance also star in Mank. It marks director David Fincher's first film since 2014's hit Gone Girl.

The 93rd Academy Awards are airing live on Sunday, April 25 at 8 p.m. ET/5 p.m. PT on ABC.