Woman raped by aliens gives birth to a hybrid, captured by mobster Al Pacheco after her birth. Subjected to various tests in the laboratory, the extra-terrestrial cub escapes and terrorizes farms by attacking mainly goat herds. Hence the myth of the so controversial Chupa-cabras. Peter Jones is a tough cop, able to risk his life to destroy the crime empire dominated by Al Pacheco. Pacheco tries to recover the monster at any cost and commits crimes, while being chased by the cop Peter Jones. However, the strange creature begins to attack human beings. Ufology and the press are also interested in the infamous mutant. But fury still stings the Chupa-cabras' eyes and no one knows how to stop their bloodthirsty.