The French don't boo, they hou. Imagine a herd of sarcastic cows, and you'll get the general idea.
At the Cannes Film Festival, vocal dissatisfaction at the end of a film isn't rare, but the reception for Nicolas Winding Refn's The Neon Demon at its first press screening was one for the history books.
A number of critics stood to yell abuse at the screen. "Tonterias!" (Garbage!) someone bellowed in Spanish.
Then the dedication "For Liv" appeared over a shot of an arid desert - Refn's wife is the Danish actress Liv Corfixen. "F*** you, Liv," someone shouted back.
What on Earth would a film have to do to provoke that kind of reaction? The answer, in The Neon Demon's case, is explosive menstruation, lesbian necrophilia, cannibalism, vomiting, gagging on knives, as well as oblique plotting, glazed, affectless performances and lots of other good stuff we go to Cannes for.
I was one of a phalanx of applauders who countered the jeering elsewhere.
Divisive and depraved, it's also one of the best things I've seen at Cannes in a strong year.
The film is set in the LA modelling business and its theme is the industry's hunger for naivety and youth.
It stars Elle Fanning as Jesse, a pretty 16-year-old who blows into town with dreams of the catwalk. She has what makeup artist Ruby (Jena Malone) describes as the "deer in the headlights look".
In other words, she's untainted flesh on the brink of destruction.
Jesse comes to realise the power of her look during a prestigious runway show that Refn and his cinematographer, Natasha Braier, push into pure, hypnotic abstraction.
Fanning's face becomes a kind of idolatrous icon, and we feel as if we're seeing an occult ritual.
After that, Jesse's rivals, played by Abbey Lee and Bella Heathcote, decide Jesse must be stopped - or at least dealt with in a way that will allow them to absorb her youthful essence.