Near the end of World War II, a ship carrying POWs captured by Japan comes under attack. Somehow, despite being shackled together at the ankles, two prisoners manage to swim to a nearby island. Saito (Dean Fujioka) is Japanese, and Bronson (Callum Woodhouse) is British, which means they obviously clash at first. But survival requires them to work together—especially when they realize the island is… well, the movie’s called Monster Islandso you know what’s coming.
With just enough backstory for these characters—the sensitive Saito has been branded a traitor, while the more brash Bronson is a known escape artist—and performances that quickly flesh them out into people who feel real despite the rather unreal circumstances they find themselves in, Monster Island clearly establishes what’s at stake from the start. We like these guys, who go from trying to punch each other’s lights out to realizing they make a good team pretty quickly.

There’s a language barrier, but the film gets around that by implying that Saito and Bronson have sort of an intuitive understanding. What they’re trying to say to each other is mostly variations on “Hey, let’s do this” anyway, especially when a couple of fellow survivors stumble onto their beach, including Japanese officers still brandishing weapons. Seeing as how both soldiers have recently escaped from prison, they’re in no hurry to be recaptured—but those worries are soon replaced by a much more vicious problem when the thing we’ve been sensing has been watching them makes its presence fully known.
There’s an almost Predator feeling to the build-up. We get stealth POV shots, a distinctive sound cue whenever the creature is lurking, and very early on we see a scaly arm try to grab Bronson. While the island is full of thick jungle, sheer cliffs, spiky trees, and at least one enormous alligator, its greatest threat is something far more cryptid in nature—or even mythological, as one of the men with the officers shrieks in fright as he realizes it’s “Fish people!”
Fish people happens to be Monster Island‘s original title—clearly it was changed to be more universal, since many Shudder viewers likely aren’t familiar with figures from Malay folklore. But a more recognizable touchstone stateside is another one of writer-director Mike Wiluan’s acknowledged inspirations: The Creature From the Black Lagoonwhich the Strongly Resembles fish.
The story setup is similar, too, as outsiders barge into an isolated habitat and disrupt the natural order of things, infuriating the resident monster holding down the top of the food chain. Just imagine the Gill-Man with many more razor-sharp teeth and claws, plus a spine-tingling vocalization, somewhere between a shriek and a wail, that echoes across the landscape. The war Saito and Bronson left behind was hell, but their new foe is just as gruesome.
And once Monster Island rips the bandage off with its creature reveal, which happens early on, the monster fully becomes the third main character. There’s no hiding in the shadows; we see it from head to toe and are made well aware of its violent power. The suit work and attendant special effects are fantastic, as the Orang Ikan chases the men around a wild environment that’d be treacherous even without a territorial sea monster.

The terrors of the plot are further enhanced by the looming specter of war, which haunts both soldiers and has also left wreckage and other debris upon the island, letting us know this isn’t the first time the creature has tangled with unwanted visitors. And while the Orang Ikan clearly the antagonist here, Monster Island also makes room to show us why it’s behaving with such aggression—for reasons the viewer will certainly sympathize with, even if Saito and Bronson don’t as they fight for their lives.
At just over 80 minutes, Monster Island offers a fast-paced race to the end. You almost wish there wasn’t a coda that contains flashbacks to scenes we just saw, but it also gives a conclusion that’s both satisfying and leaves the potential for more. And for what it’s worth, Return to Monster Island is definitely something we’d be interested in after this first visit.
Monster Island streams on Shudder starting July 25.
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