[2] It was originally to be titled Monster when the film was first announced in 1975, and again in 1977, and suffered numerous cast changes (Keenan Wynn was still billed on some of the early video releases).

Some years later, the American cement manufacturer Durado Cement dispatches troubleshooter Bill Travis to Chimayo to restore order to their manufacturing plant there: an anticorporate activist named Víctor Sánchez has been exploiting the villagers' fear of the monster to stir up hostility against Durado, which has been polluting their fishing waters in Lake Chimayo.

In the process, María has become ostracized from the villagers; a group led by a man named Carlos calls her la bruja ("the witch").

In addition, Travis must silence an American TV reporter named Patty Clark, who has been exposing the pollution of the lake.

Their father Pete, administrator of the Durado plant, is introduced to Mayor Montero and his daughter, helicopter pilot Juanita.

Sánchez meets with Carlos in a church, and together they plot to drive out the Americans, and the monster he thinks was created by the pollution of the lake.

Travis and Montero confront Clark about her reporting, and they negotiate exclusive rights to the pollution story in exchange for her temporary silence.

Travis comes up with a plan to kill the beast; he stuffs some explosives into a goat carcass, which he will hang by the detonator cord from a helicopter.

A local policeman distracts the monster by circling it with his boat, thus buying Travis enough time to retrieve the detonator and blow the creature to pieces.

The film made its debut on DVD by Shout Factory on September 25, 2007 as a part of its Elvira's Movie Macabre double feature with Blue Sunshine.

Ziemba also criticized the film's acting, "cut ‘n’ paste exploitation plot", phony monster design, and poor video quality.