Old School Campaign Deconstruction Using The Prehistoric Western Film With The Valley of Gwangi (1969) & The Beast of Hollow Mountain 1956 Cowboys, Dinosaurs, and Boot Hill

On a lazy Saturday afternoon in Connecticut way back in 1970 something or so, my world exploded in a prehistoric stampede of dinosaur fun when the Valley of Gwangi came on television. Maybe it was the fact that the Dinosaur Western wasn't that well  known or that this film came to define the Dinosaur Western genre in film. But for me in the Seventies & Eighties it came to define a friend's old school campaign world as we shall see.

My ex friend Peter was crazy about the film;"In Mexico at the turn of the 20th century, a cowgirl named T.J. Breckenridge hosts a struggling rodeo. Her former lover, Tuck Kirby, a heroic former stuntman working for Buffalo Bill's Wild West Show, wants to buy her out. Along the way, he is followed by a Mexican boy named Lope, who intends to join the rodeo on a quest for fame and fortune. T.J. is not interested in Tuck because of this, but Tuck is still attracted to T.J., especially when T.J. jumps off a diving board on her horse. T.J. finally accepts Tuck when he saves Lope from a bull and the two kiss.
T.J. has an ace she hopes will boost attendance at her show - a tiny horse called El Diablo. Tuck meets a British paleontologist named Horace Bromley, who is working in a nearby Mexican desert. Bromley shows Tuck fossilized horse tracks, and Tuck notes their similarity to El Diablo's feet. Tuck sneaks Bromley into the circus for a look at El Diablo, and Bromley declares the horse to be a prehistoric Eohippus.
The tiny horse came from a place known as the Forbidden Valley. A Gypsy known as Tia Zorina claims that the horse is cursed, and demands that it must be immediately returned. Later, she and the other gypsies collaborate with Bromley to steal El Diablo and release it back in the valley. Bromley hopes to follow the horse to its home in search of other prehistoric specimens. Carlos, an ex-member of the Gypsy tribe now working for T.J.'s circus, walks in on the theft and tries to stop it, but is knocked out.
Tuck arrives just as the Gypsy posse leaves. Carlos sees him as he is regaining consciousness. Tuck notices that the horse is missing, and sets off after Bromley. When T.J. and her crew discover Carlos, Carlos claims that Tuck has stolen El Diablo for himself. Carlos, T.J., and the others decide to follow Tuck and Bromley into the valley.
Making their way into the Forbidden Valley, Tuck, T.J., and the rest of the group meet up and soon discover why the valley is said to be cursed when a Pteranodon swoops down and snatches Lope but due to the weight it falls back to the ground. After Carlos kills the Pteranodon by twisting its neck, they spot an Ornithomimus, which they chase after in the hopes of capturing it. Just as it is about to escape, it is killed by Gwangi, a vicious Allosaurus which chases Bromley and the rest of the group. However, a Styracosaurus appears and drives Gwangi away. As Gwangi leaves, he takes the dead Pteranodon with him.
Later, Gwangi pursues the group to their base camp and they try to rope him down, but he breaks free when the Styracosaurus reappears. Gwangi battles and kills the Styracosaurus and later manages to catch and kill Carlos, but is knocked out while trying to exit the valley in pursuit of the rest of the group.
Securing the creature, Tuck and the other men in the group take Gwangi back to town to be put on display in T.J.'s show. On the opening day of the show, the dwarfed Gypsy sneaks in and begins to unlock Gwangi's cage in an effort to free him, only to be killed when Gwangi breaks free. The crowd begins to flee as Gwangi attacks, and Tia Zorina is trampled to death in the chaos. Bromley is crushed by a broken piece of the cage, and Gwangi attacks and kills a circus elephant before rampaging through the town. Tuck, accompanied by T.J. and Lope, tries to hide the crowd in a cathedral, but Gwangi finds them and breaks in. Tuck urges the crowd out through a back exit, leaving Tuck inside with Gwangi, T.J. and Lope.
Gwangi tries to eat them, but Tuck manages to distract him by stabbing him with a flag. Tuck is eventually able to throw a torch onto the floor near Gwangi, setting the building on fire. Tuck and the others manage to escape, trapping Gwangi in the burning building. Roaring in agony, Gwangi dies in the fire. Tuck, T.J., Lope, and the crowd look on to mourn the sacrifice of the burning church."
Yeah its a classic & it was supposed to be done by the effects master Willis O'Brien but he passed shortly before the film could be produce & made. Now I've written extensively of  Sir Arthur Conan Doyle's The Lost World as fodder for an old school campaign but it was also the inspiration for the Valley of Gwangi.
But the Valley of Gwangi wasn't the only film in the Dinosaur Western genre there was a film that proceeded it. The Beast of Hollow Mountain was shown on Saturday afternoons as well as on TNT cable's Monster Vision much later on;"The Beast of Hollow Mountain is a 1956 Weird West movie about an American cowboy living in Mexico who discovers his missing cattle are being preyed upon by an Allosaurus. The Allosaurus would later attack local villagers in a town, and eventually be destroyed by getting lured into some quicksand and drowning.
The first film to show dinosaurs and cowboys in the same picture, it is notable for being based on a story idea by special effects innovator Willis O'Brien. It used a form of stop motion called replacement animation to bring the dinosaur to life. O'Brien co-wrote the script under the pseudonym El Toro Estrella; O'Brien was also to have originally done the special effects for this movie, but this did not happen for reasons unknown."
There are a few great differences here between the two films that an old school Dungeon Master can exploit. The Beast From Hollow was actually my preferred film because we were way back when playing a mix of Gamma World, Boot Hill, & OD&D. The Beast of Hollow mountains has a fully realized setting with prehistoric swamps, dinosaurs, & all of the classic lost world elements. These areas were all a part of an ancient empire belonging to the Serpent men of H.P.Lovecraft & Robert Howard's creation. These lost worlds & prehistoric laboratories were scattered throughout Mexico & Central America. Their degenerate Elven attendants still at the helm even into the apocalyptic era.

This is how we designed it in my old D&D group, many of us too turns Dungeon Mastering and we were in competition with each other to see who was the better DM. This also allowed us to cover lots of ground when it came to DMing. It also meant that we had an extensive prehistoric lost world inner Earth empire to accommodate our megadungeons and prehistoric wilderness point crawls.

All of this can easily be done by using both the Boot Hill rpg & AD&D, Boot Hill gave us some great 19th century fire arms rules along with quick rules for NPC cowboys and farm hands.


By using Mutant Future plus Labyrinth Lord and LoFP's World of the Lost to fill in the prehistoric monsters & the weird lost world elements as necessary. These strange types of Lovecraftian lost world adventure locations could show up anyplace and could be found tucked away across the world. Time warps, space gates and more means could be the perfect venue to bring in PC's as needed.


There are lots of possibilities for mocking up and using this sort of a lost world campaign, the hidden legends, weird mythologies, and even the possibilities of sneaking in some Lovecraftian horrors into the old school adventure mix. As a point crawl this sort of a campaign style can't be beat with the mix of classic old school TSR era elements to form a structured and stable campaign that could be enjoyed for years to come.
Cheers & remember to keep those dice rolling!