When the Haskin family seeks refuge from Y2K hysteria in the isolated forests of the Sierra Diablos mountains, madness and terror find them there. Abducted by a vicious hillbilly clan, the Haskins fight for survival, but neither they nor the hillbilly Crawfords can comprehend the monstrous nightmare about to erupt from the bowels of the earth.

When three friends finally come to after a raucous night of bachelor-party revelry, they find a baby in the closet and a tiger in the bathroom. But they can't seem to locate their best friend, Doug – who's supposed to be tying the knot. Launching a frantic search for Doug, the trio perseveres through a nasty hangover to try to make it to the church on time.

From the cage to the big screen, the world's greatest Mixed Martial Arts Champions come together for the first time in a major motion picture. When an MMA world champion is lured into the illegal world of underground cage fighting by an elusive promoter, he quickly realizes that the only way out is to kill or to be killed.