CANNES, France – Lemmings are known for their herd mentality. So are jet-lagged journalists. A group of hundreds queued outside the Salle Debussy on Wednesday morning for Dominik Moll’s “Lemming,” the opening film of the 58th Cannes Film Festival.

After passing bag inspection and a metal-detector sweep by a team of cheery femmes in navy blue dresses, I blindly followed a throng of anxious journalists panting up to the balcony, even though I always prefer to sit much closer to the screen. Noting that lemmings are also known for throwing themselves off cliffs, about halfway through Mr. Moll’s film I considered hurtling myself from the nose-bleed section. What begins as a wry look at bourgeois decorum devolves into cheap tricks of psychological possession and oneiric confusion (sheer overkill, the Mamas and the Papas’s “Dream a Little Dream of Me” plays during the end credits).

The 30ish couple Alain (Laurent Lucas), an engineer of devices for smart houses, and Benedicte (Charlotte Gainsbourg) invite Alain’s boss, Richard (Andre Dussollier), and his wife, Alice (Charlotte Rampling) for dinner at their airy home. Bizarre Alice refuses to take off her sunglasses, accuses her husband of whore-mongering and calls her hosts pathetic. A few days later, the brittle madame tries to seduce Alain, tells Benedicte all about it – and then does something really, really messy. Even-tempered Benedicte starts to act like vicious Alice. Alain has a car accident and sees – or did he just dream it? – the titular furry creatures everywhere in his sleek kitchen.

These plot contrivances echo similar disappointments found in Francois Ozon’s “Swimming Pool” (2003), another film that contradicts its own logic – and that stars Ms. Rampling. But Mr. Ozon at least created an indelible role for the middle-aged British beauty; his “Under the Sand” (2000), in fact, essentially revived the actress’s career. Mr. Moll (who co-scripted with Gilles Marchand) simply imagines Ms. Rampling’s character as a dessicated, devouring monster.

Speaking of devouring, after leaving the Wi-Fi Cafe in the Grand Palais in the early evening, I was almost swallowed by the masses gathered around the red carpet on Wednesday evening for – what else? The public screening of Lemming.

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By the time I saw Hiner Saleem’s “Kilometer Zero,” also screening at the Salle Debussy, I had made peace with the fact that I’d be herded with the Blue Badge-sporting throngs for the next 11 days – but not with the tendency of some of my Western European colleagues to cut in line. Fearful of coming across as an obnoxious American broad, I meekly deferred to Continental brashness.

Europe looms as paradise for Ako (Nazmi Kirik), a Kurd serving in Saddam Hussein’s army during the 1980s Iran-Iraq war, in Mr. Saleem’s deeply humanist film. “Dying for Iraq – that’s stupid,” agree Ako and his fellow enlisted Kurds, one of whom lustily rhapsodizes over Anita Ekberg in “La Dolce Vita.” Like the ridiculous spectacle of a statue of Jesus being transported via helicopter over Rome in Fellini’s film, a wobbly statue of Saddam reappears in the back of a truck on the roads of Basra in “Kilometer Zero.” Book-ended by French radio reports about Gulf War II, Mr. Saleem’s movie gracefully illuminates the plight of the despised Kurds, who had their own reason for ebullience when Baghdad fell on April 9, 2003.

Making my way back to my studio, I came across a strange scene of ebullience on the Rue Felix Faure. A small crowd was cheering: Could it be Charlotte Rampling having late-night oysters? Alas, it seemed to be nothing more than a mini flash-mob, one involving lots of face paint and hugging.