It’s no secret that many of the luxuries we enjoy in the global North derive from the exploitation of and slavery within the global South. Rodd Rathjen’s Buoyancy serves as an urgent and horrifying reminder of this brutal fact, centering on indentured servitude and slavery in Thailand’s fishing industry, which serves Southeast Asia’s huge seafood export market.

Based on the true stories of Cambodian fishermen survivors, it follows a hardheaded 14-year-old country boy named Chakra in search of financial independence and riches. Chakra, who is tired and bored of his family’s modest agrarian lifestyle, decides to venture out of his village to find work in Bangkok. But he finds himself ensnared in a human trafficking scheme and, eventually, a debt trap with vicious fishing captains.

The film takes place primarily on a rickety fishing trawl, where viewers get a docudramatic look into the daily lives of Chaka and his fellow enslaved fisherman, whose diet consists of watered rice and, if you serve your master well, a measly cut of fresh fish. Rathjen shoots with minimalist subtlety, rarely employing music and letting much of the horrors unravel in the traumatized expressions of the protagonist. Much of the violence is shocking but necessarily matter-of-fact and anticlimactic, robbing audiences of catharsis or gory shock value. Rathjen’s message is clear: Chaka’s world is violently stale and horrifying.

But the film’s biggest assets are its authentic characters and performances, especially Sarm Heng in an explosive and riveting debut performance as Chakra. Then there is the fishing captain Rom Ran, played with terrifying menace by Thanawut Ketsaro. Although the relationship between the two could’ve been fleshed out more, Rom and Chakra’s chemistry is undeniably fascinating, often oscillating between enslaved and master as well as teacher and student.

Buoyancy offers an important window into the lives of Southeast Asia’s most marginalized. Stories like these are vital to illuminate much of the toiling violent labor that feeds much of the global food supply chain. Even if audiences find some of the coming-of-age themes familiar—Chakra’s teenage rebellion against his father—they will nevertheless discover much value in the film’s organic characters, setting, and urgent humanitarian message.