Black Sheep is supposed to be a horror spoof, I guess, but it is really a one-note gimmick told by a lazy and redundant jokester who keeps on repeating his punch line long after it is over and done with. I wonder why no one told writer and director Jonathan King that his horror gag of killer sheep gets old really, really fast. But then again, even producers can get lost in a high concept premise and fail to see the forest. Or maybe, based on an equally shallow joke in the movie, they relaxed and reassured themselves that they were a tree.

This film from New Zealand basically takes the premise of zombies attacking humans and puts genetically engineered sheep in place of the former. Yes, there is a laugh to be had when the meekest animals on earth become the most fearsome critters after some toxic waste falls on some sheep and sets off a plague. It comes replete with the idea that getting ravenously bitten by a sheep will turn you into one, leading to a few amusing bits where humans turn into gigantic sheep. But these killer sheep are ultimately no scarier or more interesting villains than lumbering, attacking zombies.

That leaves the human characters to do the heavy lifting of character development and this is one of the film’s great shortcomings. We get a hodge-podge of characters including Henry (Nathan Meister), who has an unusual phobia of sheep, Experience (Danielle Mason), an environmental activist who's against the domestication of sheep, her fellow activist, Grant (Oliver Driver), and a truck driver, Tucker (Tammy Davis). All of them are so thinly sketched, though, they merely become horror fodder to run this way and that.

Even the attempts at character humor feel terribly desperate and limp, no less the fact that a character’s name is Experience for no reason I can fathom. There is some beef (sorry, couldn’t resist) between Henry and his brother, Angus (Peter Feeney), who scared the former as a kid with a bloody sheepskin outfit (a scene the filmmakers think is a lot funnier than we do). But Angus’ eventual villainy representing corporate domestication of sheep is as easy as an on-off switch and the film just runs away from any social commentary it could have explored like George Romero did in his trend-setting zombie flicks.