THE BEAST OF HOLLOW MOUNTAIN 1956
Guy Madison (Jimmy Ryan), Patricia Medina (Sarita), Carlos Rivas (Felipe Sanchez), Eduardo Noriega (Enrique Rios), Pascual Garcia Pena (Pancho), Mario Navarro (Panchito)
Directed by Edward Nassour and Ismael Rodriguez
The Short Version: The story of an American cowboy, his Mexican rival, a girl, and a sprint running Allosaurus. That's the gist of this standard US-Mexico romance western that goes full blown monster movie during its last twenty minutes. It's a bit of a trailblazer being the first stop-motion widescreen cowboys vs. dinosaurs movie. Those that can make it through the first hour are rewarded with an overzealous Allosaurus and his Gene Simmons worthy tongue that whips around wildly. A warm up for the similar THE VALLEY OF GWANGI (1969), this earlier monster oater lacks the ingenuity brought to the screen by Harryhausen. The cinematography is often stunning with a music score to match. Vintage monster movie fanatics will find this of the most interest.
An American cattle rancher living in Mexico investigates the disappearances of some of his herd. Believing it to be the work of a rival named Enrique Rios, the locals fear it's a legendary monster residing beyond the sinister Hollow Mountain. Surrounded by an impassable swamp, no one who goes there returns. Said to appear during times of drought, the legend of this mysterious monster turns out to be true.
This rarely discussed oddity from 1956 makes a nice co-feature with the much better THE VALLEY OF GWANGI from 1969. Additionally, the two films make a good comparative study with the handful of similarities they share. Both movies are westerns; both are based on an idea from Willis O'Brien; both feature an Allosaurus as their central creature; both have similar locales where their title beasts reside; the dinosaurs in both movies are animated via stop-motion; and both have cutesy Mexican kids as quasi-comedy relief. 
The big difference between the two is that GWANGI knows what it wants to be. Nassour's picture flirts with monster movie cliches, and never fully commits to them till the last reel. For nearly the entirety of the first hour the film resigns itself to a standard western; although it never embraces the tropes of that genre, either. There's a fist fight and a cattle stampede, but no shootouts of any kind. However, the love triangle between Ryan, Sarita and her devious husband-to-be Enrique provides opportunities for action, but it's not forthcoming. The monster footage is far more satisfying, even though it's poorly balanced over the course of the picture.
The opening narration unveils the Mexican folklore detailing the Hollow Mountain, but it's barely mentioned afterward. At the 45 minute mark, there's an attack on one of the supporting characters; but it's not till we're an hour in that the Allosaurus makes its belated appearance where it remains onscreen for the final twenty minutes.
As compensation for a veritably monster free first hour, Jorge Stahl Jr.'s cinematography makes great use of the vast expanse of the western landscape. A number of shots feature the actors in the foreground backed by some sprawling setting behind them. The filmmakers do go overboard with the tracking shots, though. Nearly every scene has one. They often work nicely, but the trick is over-used in the extreme.
Regarding the dinosaur itself, the directors animation of the beast is well below the efforts of Harryhausen. Even so, there's some creativity during the Allosaurus action that vindicates the floppy effects scenes. Nassour's dino is exceptionally energetic. During the finale, and after attacking Sarita and Panchito in a cabin, the beast chases our hero on horseback literally sprint running across the plains and down a mountainside! 
In an odd decision, somebody thought that giving the Allosaurus an elongated tongue was an innovative touch. It flaps around so ferally, it seems to take on a life all its own.The film also benefits from an imaginative (if crazy) method of dispatching the title beast. It's a shame the first hour isn't more engaging, or even dotted with appearances by the dinosaur as opposed to cramming all the monster action into the finale.
Guy Madison was a modestly popular American actor who thrived in westerns; most notably of the TV variety where he played the lead in eight seasons of ADVENTURES OF WILD BILL HICKOK (1951-1958). Madison's movie career in the US never quite took off, but he later made a comfortable living in European cinema, particularly in western pictures.
Patricia Medina looks fetching as Sarita, the object of two men's desires. She didn't appear in much genre cinema during her career. Her only other major monster movie role was in the wacky world of the Japan-US co-production of LATITUDE ZERO from 1969 where she shared the screen with her husband at the time, Joseph Cotten.
Both Carlos Rivas (pictured at left below) and Mario Navarro (pictured at right above) turned up in the following years THE BLACK SCORPION (1957). Both actors essentially played the same roles under the directorship of Edward Ludwig in that far more satisfying monster movie with Willis O'Brien animated giant scorpions.
The ambitious Edward Nassour and his brother William ran their own production facility for a time, later partnering with the Mexican company, Peliculas Rodriguez on a few features. THE BEAST OF HOLLOW MOUNTAIN was Ed Nassour's first time as director, although Ismael Rodriguez would act as co-director here. He also took on the animation duties reportedly shoving O'Brien out of the picture, but giving him a credit on the film. 
Most monster movie fans will have little tolerance for THE BEAST OF HOLLOW MOUNTAIN. It does hold up better on multiple viewings, but knowing ahead of time just what to expect might ease the anxiety that the picture takes so long to deliver on its title. Still, the final twenty minutes are worthwhile, displaying what the movie as a whole could have been had the filmmakers invested more into the fantasy aspects of their production.
This review is representative of an MGM HD airing. THE BEAST OF HOLLOW MOUNTAIN is currently only available overseas on DVD.