Born in Israel and raised in New York, she is a Harvard-educated Oscar winner whose career ranges from action (Leon) to science-fiction (Star Wars) to arthouse (Closer) to comic book adventures (Thor). And now there's talk of a second Oscar for her title performance in Jackie, which traces the events of the week following John F Kennedy's assassination through the eyes of the iconic First Lady.

Natalie Portman in character as Jackie Kennedy

Chilean director Pablo Larrain says he only ever considered Portman to play Jackie. "She was an incredibly mysterious person, and I think Natalie has that in her eyes," he says. "That's why I wanted so many close-ups!"

For her part, Portman says that Larrain's approach to the project was provocative. "It almost felt like a dare," she says. "He kept saying, 'Either we both do this and we jump in, or we don't and we both walk away.'"

Before filming began, Portman researched the role through film clips, books and news reports. Particularly useful was the book One Special Summer, a 1951 collection of travel memories by a young Jacqueline Bouvier and her sister Lee. "It's so funny," she says. "You just see these two wild girls having a great time! It was really helpful to get this sense of who she was before."

And after she became First Lady, it was a televised tour of the White House that helped Portman get into Jackie's public persona, especially her unique way of speaking. "It's not an accent that anyone else has," Portman says. "It's this mix of mid-Atlantic faux-British that must have been from finishing school and a real kind of Long Island 'tawk'. Half of it is people I grew up with, and half is like Katharine Hepburn. But it was great to have it, because it felt like a diagram of her past."

More: Natalie Portman explains what drew her to Jackie

Portman says that the days covered in the film's script have a lot to say to everyone in the audience. "Your mourning period is also an identity crisis," she says. "It's also a crisis of faith, and a moment when you have to leave your home. And it's a moment when even as a member of the nation, not as a private person, everyone was just scared out of their minds. And she was very ahead of her time, presenting an image she wanted to show the world. So you have these different aspects of her that don't just make her our hero."

Watch the trailer for Jackie: