Twilight star Kristen Stewart, whose supernatural new movie Personal Shopper drew boos at Cannes, defended the picture as a "terrifying" look at an identity crisis.
French director Olivier Assayas' high-concept thriller stars Stewart in a movie that is an audacious mix of ghost story, murder mystery and existential drama.
• Famous films that were booed by Cannes critics
Critics at a preview late Monday booed the picture - a venerable tradition at Cannes for the riskier films - but reviews hailed an edgy performance by the American actress in which she bares body and soul.
Stewart plays Maureen, a young woman living in Paris after the death of her twin brother, who takes a job as a personal assistant to a celebrity.
The work entails fetching designer frocks at expensive boutiques for her boss. Maureen largely resists the temptation to try on the extravagant dresses but suddenly begins receiving text messages from a mystery man asking her to send him pictures of herself in the gowns.
Meanwhile Maureen also considers herself to be a medium with the ability to contact the dead. She becomes convinced she cannot leave France and reunite with her boyfriend who is working in Oman until she has communicated with her brother who died of a heart attack three months before.
Asked about the lengthy texting in the film, Stewart said it was a sign of the times.
"The fact that she can sit behind this phone and feel closer to feeling alive or something, it definitely says a lot about how we interact with each other and conversely technology. And it's a little terrifying," she said.
'Naked version of myself'
Stewart in 2015 became the first American actress to win France's equivalent of the Oscar, the Cesar, for her supporting role in Assayas' Clouds of Sils Maria.
She said her new film allowed her to test her limits as a performer. "I was surprised every day by how scary the movie was - I thought it was trippy when I read it, I thought it was dreamy and surreal and really existential, not to sound too pretentious," she told reporters.
"It's an enormous identity crisis movie and I leaned in to that. I wanted to really be the most thoughtless, present, naked version of myself I could possibly be."
Stewart has a few nude scenes in the film but the role is more revealing for her raw, natural performance, critics said.
Vanity Fair called the movie "deeply strange" but praised its star: "Stewart is not yet an actress of sprawling range, but what she's able to do in this vein, not so much playing a character as expressively inhabiting a mood, is rather remarkable."
Stewart was asked whether she, like her character, believed in life beyond the grave.
"I really don't know but I'm really sensitive to energies and I truly believe that we're driven by something," she said. "That's why this movie is scary. It's a ghost story, sure, but the supernatural aspects of it just lead you to the very basic questions (of life)."
Stewart said she and Assayas had an instinctual way of working together.
"There is a communication that is undeniable and there's a flame that he lights under my ass that is stronger than I have ever felt," she said.
Assayas, well-known for his television miniseries Carlos about the terrorist Ilich Ramirez Sanchez, said he was unperturbed by the boos at the festival.
"(A premiere) is a very intense, very powerful moment and I suppose it has to do with giving birth or something," he said.
"When you come to Cannes you're prepared for anything really, you just go with the flow."
Personal Shopper is one of 21 films vying for the Cannes top prize, the Palme d'Or, to be awarded Sunday.