'The Dropout' actress took home her first Emmy for her role in limited series Monday night.
Seyfried stunned in a strapless light pink Giorgio Armani gown as she smiled for the cameras, before heading inside for the ceremony where she took home the Emmy for Outstanding Lead Actress in a Limited or Anthology Series or Movie for playing Elizabeth Holmes in The Dropout. The dress was hand-beaded and figure-hugging and had Seyfried feeling like was wearing a suit of armor for the big night. ET's Kevin Frazier spoke to Seyfried on the red carpet, before big win, where she gushed over the epic look.
"Armani Prive," Seyfried said of the designer behind the look. "Mermaid princess. It's figure-hugging."
While she admittedly didn't know how long it took to craft the custom creation, she said it was "the best dress" she thinks she's ever worn.
"I don't know," she shared. "I honestly couldn't have thought of it -- it's like the best dress I think I've ever worn."
Ready for anything TV's biggest night has to offer, Seyfried was a knight in her own regard in the gorgeous pink gown.
"I's corseted," she described. "It's not sewn, but I will have to. It's heavy. It's like armor -- I'm like a knight."
As for how it feels to be recognized for her role on the hit Hulu series, the Mama Mia actress called it "unexpected."
"It's unexpected," she admitted. "You don't do things for this kind of reason, but it happened that people recognized it in a positive way, and it feels fantastic. It can't feel any other way."
"I can't believe I'm here," Seyfried continued. "I think the best thing about this, is that I chose something very hard and and it ended up being really hard, and really fun and people liked it, and I'm still hanging out with Liz Meriwether and Michael Showalter and my whole team, like a year later, so, we get to celebrate something that was really fun for a long long time, and it's a big time bonus."
ET spoke to showrunner Meriwether ahead of the nominations announcement, where she praised Seyfried for her portrayal of the disgraced Theranos founder.
"I just felt like, 'I can’t see the seams. I can’t see how she did it.' I was just so happy to have her," Meriwether told ET of Seyfried. "It’s a really tricky tone. I mean, there’s some comedy in the series, but it's definitely never satirical and the characters are not caricatures. And so, it was so important to find an actress who understood that and wanted to perform the character without judgment. And she just really understood that."
The 74th Primetime Emmy Awards hosted by Kenan Thompson were broadcast live on NBC and Peacock. In the meantime, check out the full winners list and stay tuned to ETonline.com for complete Emmys coverage.