I first saw this film sometime in 2007 when it was released in the United States, and recalled it being very gritty and troubling to the senses. Upon revisiting, I've found this still to be true, though now the context in which the film emerged is more clear. "Frontier(s)" is a prime example of the hard-edged French new wave horror cinema that gained traction in the early 2000s with films like "Irreversible," "High Tension," "Inside," "Martyrs," and the like. "Frontier(s)" falls in line with these films in that it creates a palpable sense of dread—it's almost unbearable to sit through, not only because of the violence, but also because the entire thing is shrouded in hopelessness. Where it differs is its overt political themes and irony. What better place for a group of young French Arabs to end up during a right-wing election than an inn owned by neo-Nazis?
The cast here is strong all around, and are a large part of what keeps the tension and pathos at such a heightened level. The film spirals down out of control in the second half, with a final act that is as gratifying as it is disturbing. Bleak, pallid cinematography and compositions, along with a brooding musical score also contribute to the film's unnerving demeanor.
All in all, I found that while I understood "Frontier(s)" more clearly on a cerebral level a decade later, it still retains the sense of hopelessness that made it an discomforting viewing experience in the first place. It's a well-made film with effective performances and cinematography. The narrative is fairly simple but not self-conscious about it, and doesn't overreach for the sake of overreaching. Overall, a bleak horror film that is commendable but somewhat of a chore to get through. 8/10.