If you're promising "high tension," then you'd better deliver, which is where Alexandre Aja and Grégory Levasseur (director, art director and co-writers) come up short. Whereas a genre film like Martyrs attempts to push the mind somewhere it doesn't want to go, High Tension aims at nothing but pure generic comfort. There are some who never tire of having the same nerves stimulated, but mine just get desensitized. And it's pretty clear that the filmmakers have spent most of their time watching slasher films to the exclusion of most everything else. Incest is no better in art than in biology. Genre insularity produces dumbed down offspring, as can be seen in the work of the Image Comics creators, who never encountered art that wasn't produced by Marvel or DC. Contrariwise, that's why the likes of Georges Franju and Alan Moore have made memorable art in well-worn genres, by adding fresh blood. But, on the plus side, Aja and Levasseur's fanboyishness did at least lead them to the ravishing gore of horror make-up maestro, Giannetto De Rossi. The man knows how to apply a saw to the face.
The film begins with Marie (Cécile De France) psychotically repeating, "I won't let anyone come between us anymore," until she begins her story for the record. This pretty much telegraphs that what's to follow is a flashback, but many viewers felt either cheated or surprised by the "twist" at the end (see Roger Ebert's thumb down) -- the twist being that the protagonist is really the killer. Marie is a thewy girl with a Caesar cut, who harbors an obsessive attraction to her delicate, promiscuous, and long-haired friend, Alex (Maïwenn Le Besco). Clearly disgusted by Alex's boycraziness, Marie's barely repressed misandry manifests itself as a feminist caricature of the ultimate macho male, what Judith Levine has labeled "the Beast" (brute, pervert, killer, etc.). Played by Philippe Nahon (who's made the Beast role into leading man material), the Killer looks like the average of every movie serial killer. As a hysterical warning against pornography, he first appears masturbating with a woman's decapitated head. In this persona, Marie butchers Alex's family as a way of "rescuing" Alex from monstrous patriarchy. And because psychosis is involved, the story is being told by an unreliable narrator, who confuses herself not only with the Killer, but with Alex (Marie imagines, or dreams, that it was her asking for help from a passing driver, when it was really her friend).
Many of the plot holes and Ebert's "violation of physics" (e.g., in one scene, the killer is shown to be driving two vehicles at once) are accounted for by Marie's schizophrenic state. The real plot problems comes when the narrative shifts out of Marie's deranged perspective to reveal to any in the audience who've yet to catch on that she's the killer. For example, cops are shown watching a video tape of her murdering a gas station attendent (the big reveal). It comes across as derelict storytelling, not the likely fantasy of a girl who's still in denial about her condition. Another example, following that scene, is Marie's flipping back and forth between her own image and that of the killer as she's chasing Alex with a power saw. Given how she continues to repeat the mantra with which the film began, Marie believes herself the protector, not the villain, so why is she remembering Alex as the one who finally stabs her, instead of repressing it, and bringing it in line with her delusional love affair?
The problem in these examples isn't with an implausible diegetic reality (as Ebert thinks), but with a fantasy too weighed down by that reality. Tension and solipsism don't mix unless you're trapped within the first-person. If objective reality enters, it should only be through the subjective filter of the ego being depicted. That's why Lost Highway maintains dread after repeated re-watchings; you can't get a sure footing. High Tension keeps deflating the fantasy by talking sensibly to its audience, which is the same crap Michael Haneke pulled with Funny Games. Ultimately, the filmmakers don't trust themselves or the audience enough to get properly lost within Marie's fugue, so the twist (which should've never been treated as such to begin with, but the narrative core) feels like a cheat cobbled onto the last act of a fairly conventional body-count film.