On the director's third feature, she relied on two superb theater actors to dig into characters it took five years to create.

Once in a blue moon you come upon a movie that is a complete surprise.

When I saw “Toni Erdmann” at Cannes, I was riveted by the father-daughter comedy, which was a hit with critics but was robbed of an award by an idiosyncratic competition jury. The film went on to wow festivalgoers and cinemas around the world, and Sony Pictures Classics opened it stateside on Christmas Day. It won the Cannes Screen International Critics’ poll, Best Foreign Language film from the New York Film Critics Circle and swept the European Film Awards, grabbing five including Best Picture; it’s nominated for the foreign-language Golden Globe and Indie Spirit awards and was shortlisted for the Oscar.

That doesn’t mean it will win. All the reasons why the movie is unconventional — organic, sprawling, shocking and hilarious — could weigh against it with more mainstream Academy voters, along with its 162-minute running time. In a telephone interview, German director Maren Ade admitted that while she had no idea the film would be quite so long and tried as hard as she could to cut the movie down to two hours, “it only felt longer,” she said. So she stuck with the film that worked best for her.

Her third film, “Toni Erdmann” took five years to get made. Ade first spoke to film and theater actress Sandra Hüller (“Requiem”) back in 2013, but she eventually landed the role of workaholic corporate strategist Ines after a lengthy audition process, cast for daughter-father chemistry with theater veteran Peter Simonischek. They spent a long rehearsal period with Ade, refining their characters, they said in our video interview below. “We spent a lot of time together,” said Hüller. “We had to get to know each other, and get on each other’s nerves.”

“Casting was rehearsing,” said Simonischek. “[Maren Ade] never did scenes from scripts, because she can write in half an hour a new scene. It’s incredible.”

Simonischek had to choose the right wig and fit seven or eight fake teeth for the father’s intrusive alter-ego Toni Erdmann. (Different choppers allow him to pop them in and out, talk, eat, or be seen by the camera from a distance.) After he loses not only his last piano student but his dog, the man chases down his consumed, work-obsessed daughter to try to pull her back to a more recognizable version of the girl he raised. “Maybe he likes to make jokes,” said Simonischek. “He likes the jokes the most. The other people don’t like his jokes so much. That’s the problem.”

Just as German Ines is caught up in her Romanian business world, actress Hüller was committed to making sure Ines was as impressive at her big corporate presentation as she needed to be. “Her job is so important to her,” said Hüller. “She must be really good at what she does, or the whole construction doesn’t work.” Nothing in the movie was as stressful for the actress: not the Easter-Egg decorating party where Ines’ father makes her belt a Whitney Houston song, not her own birthday party where she answers the door naked and insists that her guests strip down as well. It all works because Ade and her actors carefully lay the groundwork to get there.

Even now, the two actors disagree about their interpretations. This doesn’t surprise Ade at all. They tried many ways of doing things and nothing was etched in stone. There’s so much going on in every scene. The shaggy, goofy dad is dead-serious about reaching his buttoned-down achiever daughter, somehow. And she evades him. They duck and parry, changing roles and power dynamics as they go, especially during the egg-decorating party scene.

Ines is a woman in a man’s world who thinks she doesn’t need feminism, who Ade sees as almost “a gender-neutral character.” After anxiously trying to prove herself to her male bosses, eventually her father breaks through to her and she sees things the way they are and takes back the reins.

“The father starts doing what Ines wants — to grow up and do his own things — but she gets scared and doesn’t know what’s going on,” said Hüller, who admitted that there was some real-life competitive chemistry with her senior. “She doesn’t have control of the situation. The song [“The Greatest Love of All”] reminds her of the things she believes in, it’s a powerful song and message delivered there. The singing was difficult. I had to do it a lot of times, I couldn’t find the right approach … The song is really boring, and sad. Nothing happened. I found another twist after the fifth time. We felt it had to be that she fights in the song, takes back the situation, makes it her own. She’s not giving up.” (The final song is an edited mixture of some eight versions.)

“For me it’s different,” replied Simonischek. “It’s the moment when you go into song, you touch every heart. I was crying all the time. She has not forgotten the connection to her heart.”

“I don’t think so,” argued Hüller.

“This is what is touching,” said Simonischek. “To see her working in her job, to be straight and cool and all that. Then you see in the song, that she has a radical connection to her emotion. You don’t expect this.”

“I knew that, she was always there,” she responded. “He comes there and says, ‘my life is boring, I’m going to take my daughter and change her life.’ What about his life? ‘Look at what you can do. Are you happy sitting around making jokes all the time?’ … In the end he’s changing something too, it’s not that she has to be turned only.”

“They come together,” said Simonischek, “to a conversation from person to person. It’s not so easy. It is a success, you feel it.”

The incredibly long nude party sequence wasn’t that tough for an athletic actress who had played male Parsifal onstage in her birthday suit. And all the actors in the scene had to audition partly naked. “I always felt safe,” she said. “Normally you’re nude for a love scene or something sexual. We didn’t have that at all. You’re naked, what about that? It’s not a big deal. It’s not about sending any signals to anybody, or to be beautiful or stand in an attractive way. That’s the giving-up moment for Ines.”

The actors had no idea if what they were doing was funny, and Ade herself wondered if she was making a comedy. That emerged in the editing room — and in front of audiences. “Sometimes, while we were shooting, I would tell my producer, ‘Oh, fuck, this is a super-sad film,'” Ade told Eric Kohn at Cannes. “And she was like, ‘No matter what, it will be good, so we’ll have a good excuse.’ Because all humor comes out of desperation, there’s always this serious, grounded basis for the film. I was surprised how much laughter there was. If you watched the film alone on your laptop, it might not seem as funny.”

“You have to see it in the cinema,” said Simonischek.

Even at home, said Hüller, “You have to have the people, the feeling of laughing together at the problems of people. It’s a social thing.”

— Kate Erbland contributed to this story.

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