Think Fertilizer Is Yucky? Try This Kind With "100 Bloody Acres," the Australian brothers Colin and Cameron Cairnes break plenty of bones but no new ground in the camp-horror genre. Yet this fairly rote tale of rural ghouls and their passing-through prey has its own hick charm, mostly because of performers who never overplay their hands. Those who have hands, that is, as not all the actors make it to the end of the movie with a full complement of limbs. For that we can blame the fertilizer kings Reg and Lindsay Morgan (Damon Herriman and Angus Sampson), whose popular blood-and-bone product contains a secret ingredient. Up to now, these composting geniuses have settled for random roadkill - a kangaroo here, an accident victim there - but pickings are slim. So when Reg happens upon three young travelers whose car has broken down, he decides it's time to be proactive. Favoring sight gags over scares, this comedy of errors charges from the Morgan barn, where the rattle and hum of a whole-body mulcher awaits our three prisoners, to a variety of scrubby outdoor locations. Anna McGahan shines as a coquettish captive trying to woo the simple-minded and improbably squeamish Reg, while Mr. Sampson gives the monstrous Lindsay a brutish single-mindedness. Lindsay may suffer from what his decrepit Aunt Nancy describes as "an anger thingy," but it's his thing for Aunt Nancy that provokes the film's most disgusting scene. Even that vat of noxious slurry idling in the barn is easier on the eyes.