A letter from a son, dead from suicide, asks that his divorced parent go on a trek across one of America's hottest zones, Death Valley.

The premise of Valley Of Love (NC16, 92 minutes) is "perverse and vile", says French actress Isabelle Huppert, 62, who plays the mother, opposite Gerard Depardieu's father.

"The claim is in the letter that the son was not given attention by his parents as a little boy. It's a letter full of admiration as well as reproach... it's an expression of power of a child over his parents," she tells The Straits Times on the telephone from Paris.

Huppert, who with Depardieu ranks among the most globally well-known talents France has exported, talks about the guilt that accompanies the act of being a parent, a guilt that can be exploited by the child.

"He was missing something from his parents and now that he is dead, he is going to have them pay him back. It's a way of power, but also of love," she says.

That mix of tones - guilt and love, grief and hope - pervades Valley Of Love, which was selected to compete for the Palme d'Or at the Cannes International Film Festival this year.

It is written and directed by novelist and film-maker Guillaume Nicloux, best known for last year's The Kidnapping Of Michel Houllebecq, a fictional film about the famed novelist, with Houllebecq playing himself.

Huppert has worked continuously in television and film since the early 1970s, both in French and English.

Directors such as Ned Benson (The Disappearance Of Eleanor Rigby, 2013) and Niels Arden Oplev (Dead Man Down, 2013) have made use of her face, known for displaying depths of emotion with the subtlest of expressions.

Valley Of Love pairs her with Depardieu for the first time since 1980 drama Loulou, a Cannes contender for which she was nominated for a Best Actress Cesar.

It was as if the break of 35 years never happened, she says.

"It was exactly as if it was the first time - it felt very normal and very simple to work with him. I don't know why we never worked together again after Loulou, but hopefully we'll work together again," she says.

In Valley Of Love, the two actors play a version of themselves - the characters are actors, named Gerard and Isabelle, who are recognised by other tourists - but Huppert insists that other than superficial traits, there is no resemblance between what they play and their real lives.

But one thing was too real: the landscape of California's Death Valley, with its intense heat.

The characters refer to its punishing effects.

For Huppert, not much acting was needed to show how the climate was wearing her down.

But it was worth the risk of heat stroke. The area has an otherworldly beauty that fits with the ideas in the film.

"The heat never stops. It's there all the time, 24 hours. But it's a beautiful place, like the surface of the moon. The immensity of it shows the loneliness, the feeling of being lost. There is a special connection between you and the universe," she says.

• Valley Of Love will be screened tonight (Dec 11) at GV Plaza, 9.30pm.
• It is also screening tomorrow (Dec 12) at 9pm at the Alliance Francaise as part of the Rendezvous With French Cinema festival. Tickets are $13 at www.rendezvouswithfrenchcinema.sg