Isolation is the promising feature debut from Irish director Billy O'Brien, who smartly eschews cheeky horror shenanigans in favor of a straight-laced approach to his admittedly silly subject matter. The result is a genuinely scary monster movie that builds tension the old fashioned way, with careful pacing, editing and a refreshing lack of in-jokes. Even with a premise that reads like concentrated cheese on paper — mutant cow fetuses run amok — O'Brien proves himself capable of delivering a gratifying horror experience.

Genetic experiments are conducted on a remote farm in an effort to make bovines more fertile. The farm's owner enlists a pair of trespassers to help deliver a calf in the middle of the night, only to have to kill it upon discovering its aggressive tendencies. Dissecting the dead calf reveals further cause for concern as it is found to harbor a number of strange parasites. One of these creatures escapes and begins feeding on the farm's livestock, not to mention terrorizing its inhabitants.

Fighting for their lives, the farm hands must decide who poses the greater threat — the ever-growing blood-thirsty mutant or the crazed scientist intent on "quarantining" the farm. O'Brien treats the film with humorless sincerity and avoids the nerdy reference-speak that plagues many contemporary genre films. Isolation keeps the red stuff flowing with satisfying physical gore effects that punctuate tightly-scripted creep-out sequences. Though not possessing the edge-of-your-seat suspense of The Descent, O'Brien's freshman effort nonetheless hits the mark with its spooky on-location farm sets and quality sound design.

Isolation will not win any awards for originality, as it is similar to any number of mutated-creature-gone-wild thrillers from the 1980s. It remains gravely serious throughout, however, and steers clear of cheap scares in favor of tried-and-true horror setpieces. Only the goofy rock song that plays during the ending credits spoils the mood with its lyric "I'm gonna make you love me 'till the cows come home." Even if those cows stay out all night, Isolation is still a worthwhile trip to the farm.

Thumbs Up. Old-school scares and tight pacing make this a mutated cow fetus worth cozying up to.