Diane Kruger and Jason Wu on Their New Collab and That Time They Partied at Coachella

If the key to a successful union is finding common ground, then Jason Wu and Diane Kruger are ready to make their relationship as designer and muse official.

“We’re both brutally honest,” says Wu, who has dressed Kruger for many red-carpet events, including her latest appearance at the Cannes Film Festival for her best-actress-winning (and Oscar-buzz-generating) performance in the German thriller In the Fade. “That’s why I’ve always gotten along with the Germans—she’s very straightforward.”

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The duo are so often of one mind that their new collaboration, a 1940s-inspired capsule for Wu’s more accessible collection, Grey Jason Wu, seemed all but inevitable. Conceived while the friends were vacationing together in Mexico, the six vintage-bombshell pieces were items Kruger really wanted in her own wardrobe, like a slim-fitting jumpsuit dressy enough for the red carpet, and a double-ply tank top to pair with palazzo pants.

With the collection arriving in stores this month, Wu and Kruger took time to reminisce about some of their favorite looks, as well as their shared love of music festivals, home décor, and cats.

Diane Kruger:We first met in 2009. I was looking for a dress for Cannes, and I always watched the up-and-coming designers. I asked if I could try on a dress, and he showed up at a photo shoot I was doing to fit it himself. To be honest, I didn’t know right away that he was actually the designer, because he looked about 12 years old.

Jason Wu: I think she’s flattering me. I looked 18.

DK: No, for real, he looked so young. And I had read that he had just dressed the First Lady.

JW: When I work on a project, I kind of go all the way. I even carried a dress to one of her movie premières this year. I couldn’t just stick this thing in a FedEx box.

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DK: I love people who do everything themselves. He’s refreshingly not blasé about the opportunities he has had. What started out as a working relationship has grown over the years into a real friendship. In fact, we’re neighbors now in New York City.

JW: At the time I was like, “Oh, Diane Kruger, she has the best style,” and I always wanted to dress her. But I couldn’t even afford messengers back then, so I had to do everything myself. I even painted my own studio and fell off the ladder. I was black-and-blue for weeks. I’m not a good painter.

DK: Now I trust him blind. This year at Cannes, I wore a dress from his 10th-anniversary collection that was just so gorgeous, but it was transparent, so it obviously wasn’t going to work for the red carpet. It turned into such a labor of love to find the perfect nude lining.

JW: Oh my god, we went through so many. And we actually put Swarovski crystals inside the bottom of the train so that it would capture the friction of the carpet. Otherwise, the tulle would have gathered in a puddle.

DK: With Jason there’s no middleman. If I ask a designer to make a dress for me, I’m not going to look at 15 other dresses at the same time. If I say I like a dress from the get-go, I’m wearing it.

JW: We really bonded when we first went to Coachella together. I don’t usually fare well outdoors and in crowds, but the key was to leave the VIP section and go out onto the main floor. Our friendship just evolved. We spent Christmas together this year in Mexico, and on the beach she was like, “I need some jumpsuits.”

DK: I kind of wanted him to say, “I’ll just make you a couple of whatever you want and you can wear them.” And then it became, “Why don’t we make a capsule collection?” So these are things I really wanted: the jumpsuit, a velvet dress, and more casual pieces like striped pants and a white tank. I mean, I’m not a designer—don’t get me wrong. But I know what I want to wear, right? So I would send him vintage references or pictures of people in the street or Marlene Dietrich.

JW: The first time I custom-made something for Diane was for the SAG Awards after Inglourious Basterds. She wanted the silhouette to be perfect. One of the shoulder straps turned out to be so tight, she couldn’t move her arm.

DK: We won for best ensemble, so we all got these superheavy trophies, and in every picture I look like I can’t even lift the thing.

JW: But the silhouette was great, and that’s all that matters. We have so many stories like that.

DK: One year I went to the Met Gala with him, and my top was this fully sequined bodysuit, but I wanted it to be super tight, so he had to sew me into the thing. To get out of it, we went into The Mark hotel and locked ourselves in the bathroom so that he could cut me out.

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JW: Only we had no idea somebody was inside. We heard a flush, and then this girl walked out and was like, “Are you all going to one of those parties?”

DK: And I’m literally butt naked ...

JW: It’s those kinds of experiences that really became the inspiration for this capsule. It’s not all about me being a designer, her being an actress. We’re just really good friends. We both love interiors too. And we both love cats. I have two, Jinxy and Peaches.

DK: I have one, Hobbes. He’s gray and white. One thing Jason’s better at than I am is decorating. His house is gorgeous. Gray, gray, gray, gray.

JW: Gray and tan. Everything matches the cats, so you don’t see their hair. That’s always been the trick. It works.

For more stories like this, pick up the November issue of InStyle, available on newsstands, on Amazon, and for digital download Oct. 13.

Photographed by Tom Allen. Fashion Editor: Ali Pew. Hair: Christopher Naselli for Starworks Artists. Makeup: Gita Bass for Starworks Artists. Manicure: Deborah Lippmann for Starworks Artists. Set design: Cooper Vasquez for The Magnet Agency.