“This film is based on historical events recorded in Annals of Joseon Dynasty,” we’re told at the outset of Monstrum. It seems like the Joseon Dynasty is an era of Korean history that’s ripe for monstrous adaptation. Earlier this year, we had the second season of the absolutely phenomenal Netflix series Kingdom, which took the era’s political strife and mixed it with a zombie plague that illuminated the politics and callousness of the ruling class. And now there’s this new Korean import that takes a more pulpy, horror-adventure bent to a similar story of political strife, plagues and, of course, monsters.

The opening lines explain that King Jungjong (Park Hee-soon) was placed on the throne after the previous leader was dethroned by an opposing faction in the court. But now, Jungjong’s officials, who originally put him on the throne, have turned against him and are actively trying to send the nation into turmoil. At the same time, a deathly plague raced through the kingdom and decimated the population.

Ten years later, rumors run rampant through the kingdom of another threat: a monstrous creature that is preying on the various townolk.

Jungjong knows that this creature is a fabrication. A lie made up by his prime minister Sim Woon (Lee Geung-young), who has been scheming for years to dethrone him. Sim Woon loudly tells the king that, “Disasters plague a nation that has no leadership.” King Jungjong wants an investigation into this supposed monster roaming Mt. Inwangsan, so he sends a group of men to find Yun Kyum (Kim Myung-min), the king’s disgraced and exiled general.

Yun Kyum has been living in relative obscurity with his adopted daughter Myung (Korean popstar Lee Hye-ri) and his best friend and pseudo-brother Sung Han (Kim In-kwon). Here the more comedic side of Monstrum shines as Yun Kyum and Sung Han bicker like a married couple while failing miserably at hunting. Myung, a skilled huntress herself, lovingly mocks the two of them: “Those two can’t even slaughter a rabbit,” she incredulously scoffs at one point.

But their little slice of paradise is ruined when Officer Hur (Parasite’s Choi Woo-shik) shows up with King Jungjong to send them on their quest.

What follows is a mix of monster movie, mixed with political espionage and a fantastical noir-esque mystery of whether there is a monster or if it is just the work of the Prime Minister. A lot of the narrative is centered around this investigation into fact versus myth at a time when the people in power hold the knowledge from the lower classes while simultaneously using them as pawns. Because we know this is a monster movie (and the marketing clearly establishes it as such), we’re already a few steps ahead of our heroes and so it can make the first part of the movie feel a bit overlong.

Eventually, it gets to what we want to see: monstrous mayhem. And boy is there a lot of it.

Monstrum reminds me of the pulpy fantasy movies I’d watch growing up in the 80s, like The Sword and the Sorcerer and Excalibur and even Dragonslayer. The kind of movie about duplicitous politicians and dark, dank caves that must be explored and the kind of giant monster that feels larger-than-life in character. Bodies will be tossed, gnashed, stomped and torn asunder. The bad guys must be punished, the good guys must prevail and it’s all just some big budget excitement.

That said, the CG monster is a bit iffy at times. The actual creature design is stunning and incorporates Korean mythological monsters with the idea of the plague and it actually does feel like it has a presence on screen that some big budget American movies should take note of. Sometimes, it looks a bit on the cartoony side and it can ruin the immersion. But it’s still a solid design...I’m just always going to wish for a time of more practical effects.

Like a lot of Korean horror movies, it balances multiple tones and genres. Some films, like Bong Joon-ho’s Parasite or The Host, balance that tone perfectly. Unfortunately, it’s a bit wobbly in Monstrum. One moment, our heroes are plummeting to sure death into a dark and dank cave filled with carcasses and bones of previous meals. The next they’re trying to stay silent while the creature literally farts in their faces and sneezes on them. Meanwhile, the idea of a monster and a plague running rampant through a kingdom while the ruling class tries to use it to continue sowing doubt and fear among the populace in order to control them is…well, it takes on a different hue right now, from quarantine.

This mix of fantastical whimsy and stark political critique, like the monster, doesn’t always coalesce into perfect union. But man, once it gets going, it’s a complete blast.