A lone-wolf scientist sequestered in a mansion near a small desert town arouses the suspicion of the town's doctor when his lab assistant is found dead from a case of acromegaly which took only four days to develop. As the doctor investigates, aided by the scientist's new, and very female, assistant, they discover that, far worse, something much larger and hungrier than it ever should be, is devouring local cattle - and humans - in increasingly large quantities.
Animals are used as test subjects for scientific experiments. There is a shot of a rabbit squeezed into a too small cage to imply it has grown giant. The rabbit is breathing quickly.