Dour, moody, petulant, very masculine and unsociable loner abattoir worker Marcos (a fine, low-key, creepily nonchalant performance by Vincente Parra) and his peevish, unhappy girlfriend (the lovely Emma Cohen) take a ride in a taxi one fateful night. The irritable cab driver tosses them out when they start making out in the back of his taxi. Marcos and the cabbie have an altercation which results in the cabbie being killed. Marcos' girlfriend wants to tell the cops. Marcos, who's distrustful of authority due to his lowly working class social status, throttles his girlfriend in a fit of pique. Pretty soon Marcos becomes extremely paranoid and begins to kill every last person who suspects him of being a homicidal maniac (Marcos even whacks his own brother with a wrench). Marcos strikes up an uneasy friendship with an earnest, but suspicious gay neighbor. Things get even more tense. Meanwhile, Marcos chops up the corpses residing in his spartan, squalid rathole abode and disposes of the body parts by incinerating them in the slaughterhouse furnace.<br /><br />A grave, gruesome, exceedingly unnerving and disconcerting depiction of how severe self-loathing and one's miserably meager station in life can feasibly drive you murderously around the bend (Marcos registers strongly as a hauntingly sullen and scarily twisted proletarian anti-hero), this dark, stark, deeply disturbing and harrowingly plausible psychological horror portrait of everyday gratuitous violence, repressed sexuality (there's an edgy air of homo-eroticism apparent in the relationship between Marcos and his meddlesome neighbor), and seething, volatile little guy angst makes for a very queasy and unsettling viewing experience. The late, great Eloy de la Iglesia's taut, austere, fiercely humorless and deliberate direction, ably assisted by Raul Artigot's grainy, gloriously unadorned no-frills cinematography, Fernando G. Morcillo's spare, spooky, nerve-jangling score, occasional outbursts of hideously graphic and genuinely shocking violence, gradual pacing, an unsparingly solemn tone, and properly subdued naturalistic acting from the uniformly solid cast, creates a frightfully squirmy and sweaty suffocating gloom-doom atmosphere which ultimately delivers one hell of a potent and lingering kick-you-in-the-gut wallop. Anchor Bay's typically up-to-par DVD offers a nice widescreen presentation with the trailer as the sole extra.