Kumiko, the eponymous character in the new movie "Kumiko, the Treasure Hunter" played by Rinko Kikuchi, is a seriously challenging individual to inhabit.

Obsessed with "Fargo" and convinced it's a documentary, she travels to the barren Upper Midwest from Japan on a search for the hidden treasured buried by Steve Buscemi's character in the Coen Brothers' classic.

Why on Earth would someone do this, and how do you come to understand them?

"She is a socially isolated character," says Kikuchi, 34. "But as you get toward the second half of the movie [on her treasure hunt] she really becomes more alive."

Kikuchi, an Oscar nominee for "Babel," is a true international star; she's filmed movies ranging from "Pacific Rim" to "The Brothers Bloom," across the United States and all over the world.

None of those experiences prepared her for the harshness of Minnesota in the dead of winter, where she shot the film by David and Nathan Zellner.

"It was super, super cold. That was the coldest place in my life," she says. "But they gave me a lot of warm things to wear. I am now prepared to shoot pretty much anything where it's really cold. It does not threaten me."

The discomfort appears to have been worth it. The movie, opening in theaters Wednesday, earned Kikuchi an Independent Spirit Award nomination and has been hailed by critics. Her star is still rising. "For a film that is so dear to me to be something that is so widely accepted is very gratifying," she says.