Portman certainly nails the accent, but she clearly has to do some serious acting work, too, portraying the highs and lows in the life of one of America's most recognizable figures.
The teaser starts with a sweet rendition of Richard Burton singing Camelot, but the song morphs into a haunting collection of strings as the mood shifts, revealing unsettling images: the first lady washing blood out of her hair; the chaos at the hospital after John F. Kennedy was shot; and Jackie sitting beside her husband's casket, still wearing her pink Chanel suit.
So far, the reviews have been sublime.
"Extraordinary in its piercing intimacy and lacerating in its sorrow, Jackie is a remarkably raw portrait of an iconic American first lady," the Hollywood Reporter raved.
The movie is the English language debut for Chilean director Pablo Larraín, who wowed critics this year with Neruda, his unconventional look at Pablo Neruda's life.
Similarly, Jackie steers away from the traditional biopic formula.
Most of the movie concerns the aftermath of Kennedy's assassination and the first lady's attempt to plan the perfect funeral - one that can cement her husband's legacy.
But there are flashbacks, too, and shard-like scenes, told out of order, are meant to do double-duty by giving the audience a sense of both the political machinations that were happening just after Kennedy was killed and who exactly Jackie Kennedy was.
"We know superficial things about her, about the way she dressed or the way she did her hair," Portman said during an interview with the Hollywood Reporter. "But this really goes into her as a human being and her psychology."
Of course, to do that, screenwriter Noah Oppenheim had to make some guesses about what was going through Jackie's mind.
He has said that he's fascinated by the vast difference between the way people act when they're in the public eye and who they are behind closed doors. That does make for intriguing cinema, and who wouldn't want to know what Jackie was thinking? All these years later people are still transfixed by the Kennedys.
But the approach will also open the movie up to criticism from naysayers who like historical movies told with just the facts. Just about every movie that's been based on a true story in recent years has been pilloried because it took liberties with the truth.
In one scene, Jackie is shown drinking heavily and popping pills alone in the White House.
It's a far cry from her controlled image, and one that some viewers will no doubt try to challenge.
The risk was apparently worth it for Fox Searchlight, which snapped up the movie after its Venice premiere.
The studio was "emboldened by the attention Natalie Portman will surely receive at Oscar time for her silky, steely portrayal of a woman quietly but firmly taking control of her late husband's myth," wrote Washington Post film critic Ann Hornaday.
And Portman isn't the only one worth watching. The movie took home a screenplay prize at Venice, raising Oppenheim's profile as we head into awards season. Peter Sarsgaard is also getting praise for his portrayal of Bobby Kennedy (Danish actor Caspar Phillipson plays the president, though his role is fairly limited), as is composer Mica Levi, who's best known for her memorable score in Under the Skin.
All of the buzz is happy news for Fox Searchlight, which happens to be the studio that snapped up The Birth of a Nation for a record sum during this year's Sundance Film Festival.
As that movie's awards prospects look dimmer all the time, Jackie is starting to look like a surer bet.