By Nigel Smith
January 26, 2018 03:12 PM

You better believe being cast opposite one of the most revered actors of all time is a little intimidating.

“I was s— scared!” Vicky Krieps, 34, tells PEOPLE of playing the rebellious wife of Daniel Day-Lewis’s perfectionist clothing designer in Phantom Thread.

As filming went on, “I let go of my fears,” says the Luxembourg native, “but the intensity stayed for all three months of shooting.”

A relative unknown in the U.S., Krieps made a big impression in Paul Thomas Anderson’s acclaimed period romance — her first major English-language film. The film surprised on Tuesday, earning six Academy Award nominations, including Best Picture, Best Director and Best Actor for Day-Lewis.

Here are five things to know about the breakout star.

She’s living the “dream”

Asked what the past few months have been like, Krieps likens it to “a dream.”

“I wake up in the morning and I need some time to realize where I am and what happened the day before,” she marvels.

Phantom Thread
| Credit: Laurie Sparham/Focus Features

She is starstruck by Gary Oldman

One her biggest fans is the Darkest Hour Oscar nominee, who’s up against Day-Lewis for Best Actor.

“I bumped into him at a Focus Features party and he said he liked my performance,” she recalls. “That was very strange because I’m a huge fan of his work. To me he’s a master of his art. Even only that he knows my work, he didn’t have to like it, that would already be overwhelming.”

She tried to forget she was making a movie with Day-Lewis

“It was intimating in the beginning,” she recalls of working with the actor. “I didn’t see him before and he was preparing on his own. So I remember being very scared although I kept telling myself it was going to be fine. I tried to forget everything I knew about him. I tried to forget I was making a movie, to give as much authenticity as I can. I wanted to be in the moment.”

She had no idea Day-Lewis was set to retire

Krieps says Day-Lewis’s decision to retire after Phantom Thread came as a “complete surprise” to her. “My neighbor came to me and said, ‘I read he’s stopping acting on the internet,'” she says. “I was definitely not expecting this to be what he is planning. It’s a very private decision — and I do respect it. He’s an individual as everyone is and I find it’s your duty to be true to yourself. If this is his truth then this is what he should do.”

Credit: Stefanie Keenan/Getty

She wasn’t so fond of wearing gowns in the film

“I learned to appreciate clothes more and be able to enjoy them,” she says of wearing period gowns in the film. “Dresses are something you can enjoy. But I also found out why I like my pair of trousers. I remember shooting and thinking, ‘I can’t wait for the 60s to come!’ Because it really was imprisoning these dresses. As beautiful as they are they’re really uncomfortable. They’re so tight on the waist. In the evening I was always very happy to get back into my jumpsuit.”

Phantom Thread is now in theaters.