The Beast of Hollow Mountain is a 1956 weird west horror film about an American rancher living in Mexico who discovers that his missing cattle are being preyed upon by a dinosaur.

In spite of these tales and possible perils, American cowboy Jimmy Ryan leads his business partner Felipe and their worker Manuel into the area one day in search of lost cattle.

Back in town, Jimmy passes by a cantina where a young boy Panchito awaits his father Pancho, who has been drinking copious amounts of tequila to forget his deceased wife.

As the two are leaving, a gang of young boys throw firecrackers at them, causing Pancho to fall off his horse and get dragged across the ground.

While the two are talking, Don Enrique, an abrasive caballero engaged to Sarita, arrives and demands Jimmy leave the country and return to Texas.

The next morning, Jimmy and Felipe read a note from Manuel and the other two ranch hands saying they are afraid of the curse of the Hollow Mountain and have quit.

Pancho and Panchito inform Sarita that Jimmy's men left after being both threatened and bribed by a mysterious man who gave them orders on what reason to leave behind.

Despite concern for the growing conspiracy against Jimmy, Sarita follows him to the top of the nearby mountain to apologize, and the two share a moment.

While Panchito guards the horses, the three men head out and find the body of another missing cow, once again drowned in the swamp.

Jimmy decides to get a loan from the bank to ensure the smooth charter of the cattle shipment, so he and Felipe head to town.

As he leaves unsuccessful, Felipe reveals that two men-the men secretly hired by Enrique-are willing to work for them and wait until after the shipment for their double payment.

The next day, the festival is going on in town, and while workers are busy gathering food and putting up streamers and displays, Panchito sullenly mulls about, refusing to talk to anyone.

At the ranch, the beast from Hollow Mountain, a Tyrannosaurus rex, arrives and kills one of the cattle, forcing the others into a stampede, much to the surprise of Enrique's men.

Enrique's men race to him and Don Pedro ahead of the cattle who begin stampeding the village, causing much panic and disrupting the festival.

While Jimmy is hiding, he notices Enrique's arrival and tries to warn him, but the sight of the T.rex causes his horse to buck and throw him off.

Jimmy is saved by the arrival of Sarita and Panchito, who have gathered Felipe, Don Pedro and other cowboys who fire at the Beast to distract it.

Jimmy throws his lasso around a tree branch, hoists himself upwards on the rope, and begins to swing back and forth, barely out of the T.rex's reach.

[2] The story was developed from an original idea from special effects innovator Willis H. O'Brien,[2] who had earlier fleshed out the concept into a script titled The Valley of the Mists, which he had not been able to get made into a movie.

O'Brien was in talks to do the effects for The Beast of Hollow Mountain,[3] but that responsibility was ultimately given to Jack Rabin, Henry Sharp and Louis de Witt instead.

Filmed in color and in CinemaScope at Churubusco Studios in Mexico City, The Beast of Hollow Mountain was one of the few American–Mexican co-productions of the 1950s.

[3][4] The Beast of Hollow Mountain was satirized in a Season 11 episode of Mystery Science Theater 3000, released on April 14, 2017, on Netflix.