And what did the always candid Seyfried have to say when Givenchy offered her the highly coveted gig?
"F--k yeah," she tells WWD. "It's an honest collaboration. I'm proud to be a part of [the brands I'm involved with] because what they do is really cool, especially Givenchy -- they're so artistic. And I feel like I have a foot in the fashion industry now."
Her campaign will include both print and TV ads, with the print ads hitting magazines in October.
But don't expect any of her own celebrity fragrances anytime soon.
"They're hard work, and the more you do, they take away from your work as an actor," she says. "I'm doing these two campaigns [she also represents skincare line Clé de Peau Beauté] because I care about them and the people involved. They're great things to be attached to."