TREMORS 4: THE LEGEND BEGINS

In 1889, the inhabitants of Rejection are completely dependent on the income from a nearby silver mine. One day, water from a hot spring causes graboid eggs to hatch, resulting in the death of 17 miners. Hiram Gummer, great-grandfather of Burt Gummer and the mine's owner, arrives in town to assess the situation. After juvenile graboids that can shoot out of the ground (later dubbed Dirt Dragons) attack his camp one night, he is shocked by their presence. One of his companions, Juan, kills one with a pickaxe, and the pair escape while four others accompanying them are killed.

Inexperienced with and not fond of firearms, Hiram puts out a call for a gunfighter, to which Black Hand Kelly responds. Hiram and Kelly do not get along well, though Kelly succeeds in conveying to Hiram some of his attitude towards firearms and life in general. Hiram, Juan, and Kelly discover that a total of four graboids have hatched, including the one Juan killed earlier. Kelly is later eaten alive by a now fully grown graboid. Hiram decides to abandon Rejection and tries to convince the townsfolk to do the same, but they refuse to leave their homes. They also force him to give them the silver mine, threatening to alert potential buyers to the danger if he sells it out from under them. In Carson City, Hiram learns of a telegram revealing that the fully grown graboids have made it through the pass and are headed for the town. Changing his mind, he buys weapons with the last of his valuable belongings, heads back to Rejection to lead a last stand against the graboids, and helps the town prepare itself.

After two graboids are killed, the third one adapts and avoids all of the traps. Hiram tricks it into coming to the surface and then attaches it by the tail to the flywheel of a steam traction engine. The graboid is reeled in and slammed against the front wheels and boiler with such force that it is explosively decapitated. With the creatures dead, the town decides to keep their existence secret for fear that no one would settle in the area if it were known, and to use the mine's proceeds to pay for their belongings. Hiram settles in Rejection (renamed Perfection), building his home in the same place where his great-grandson Burt's would one day be. He is also given a Colt 1865 Gatling gun and begins target practice, enjoying it.

Hiram returns to lead the townsfolk in defeating the remaining graboids, ultimately killing the last one using a steam traction engine. The town keeps the creatures' existence secret and Hiram settles in Rejection, which is renamed Perfection.

The finale sees Hiram embracing his role as a protector, overcoming his aversion to firearms, and helping secure the future of the community. The decision to conceal the graboid attacks sets up the lore for the original Tremors, while Hiram's newfound place in the town closes the prequel with a nod to the Gummer legacy.