There's something deadly stalking the eerie San Luis Valley in Colorado and New Mexico.

A mysterious entity that preys on cattle, mutilating them with surgical precision.

It's a gruesome phenomenon that's been going on now for more than twenty years, and one that's got officials and ranchers truly baffled.

Animal X headed to northern New Mexico to investigate the many theories on the attacks including claims that extra-terrestrials are the cattle surgeons.

Others say it could be the macabre attacks could be the work of satanic cults practising animal sacrifice. Whoever or whatever is responsible they have certainly covered their tracks and lack of evidence is just as mystifying as the mutilations themselves.