In Yeon Sang-ho’s Colony, the zombies develop collective intelligence after overcoming individuality as human beings and achieving collective consciousness. The introductory sequence of the film hints at communication through pheromones, like that of ants, but it brings to mind Niklas Luhmann’s systems theory instead. This theory suggests that an individual’s genuine thoughts can only be conveyed to others through social systems. Since each of us holds a system of thought that is closed off from the others, we cannot directly transfer our thoughts or feelings to others, and what we call communication is the work of encoding that system into language and behavior according to social convention and then interpreting what comes back, which means it can never be anything but indirect. In other words, communication is a socially constructed system of representation, which prevents us from fully understanding what others are thinking.

Set against the backdrop of a bioconference in a high-rise building, Colony unfolds a dystopian narrative that begins with a terrorist threat by Yong-chul (Koo Kyo-hwan), who claims to be a human vaccine against bioterror. Unaware of this fact, Se-jeong (Gianna Jun) and her ex-husband (Go Soo) attend the bioconference. Following the event, Yong-chul intentionally approaches the CEO of a biotechnology company, who appears to be his former boss and who had taken credit for Yong-chul’s idea. Yong-chul injects him with a zombie virus that ultimately forms the colony, allowing infected people to share every feeling and sensation and to follow their leader, Yong-chul. Alongside other survivors, including a police officer, a building security guard, and his paraplegic sister among others, Se-jeong and her group struggle to survive the infection and capture Yong-chul to thwart his plan.

The difference between Colony’s zombies and those in other films is that the zombies in Colony absorb new information from every node of the infected, leading the audience to wonder how much the colony knows about the survivors and the circumstances. In the beginning, the zombies cannot tell human beings from human-shaped paper cutouts, but once they evolve and learn what a physical human being actually is, the survivors try to disrupt the zombies by providing them with false information about human beings. When the survivors overlook the fact that the zombies are sharing and evolving every hour, they are detected by zombies and fail to escape from the infected building.

At this point, the characters in Colony become less distinct. Since the narrative of the film follows the survivors as they respond to new zombies and plan their escape again, it leaves little room to develop the survivors’ personalities. Se-jeong keeps the composure of a scientist as she works to understand the outbreak and respond to it, but the role concentrates on catching the zombies’ reactions and explaining them rather than bringing the character’s own temperament forward. The early scenes suggest that Se-jeong is stubborn and holds firm views of her own, but the portrayal that follows keeps her static in the position of observer and analyst, which leaves a question about the character herself. It is fortunate that Jun’s screen presence makes up for this weakness, since another actress would have had difficulty carrying a role written this thinly. In addition, among the survivors, the office worker in a suit repeatedly complains without ever receiving proper focus, and the relationship between the bullied and bullying high school students builds tension at moments yet never brings out the character of Se-jeong or Yong-chul, which raises the question of what the supporting roles are meant to do in this film.

What makes the narrative of Colony distinctive is the moment when Se-jeong and Yong-chul finally come face to face. Meeting him, Se-jeong realizes that the invitation to the bioconference had come from Yong-chul, and what comes out is that his attack originates not just in grievance or misconduct at the biotech company but is also deeply rooted in his father’s suicide, which turns out to be connected to Se-jeong. Having watched his father on the phone with her, Yong-chul came to feel that his father’s death was caused by the impossibility of direct communication between people, and as a bioengineer he went on to study a way of linking feeling and thought directly from person to person without language as the medium. In Luhmann’s terms, Yong-chul set out to use engineering to correct the incompleteness of “the system of communication” that holds human society together, and the colony was what that correction produced.

This sequence, which lays out Yong-chul’s past along with his motive for the attack, makes clear that Colony succeeds not just as zombie action but also as a story about the problem of communication. The same failure appears between the scientists and the government officials outside the high-rise, who work out a response while failing to communicate with each other. The officials tell the scientist Gong Seol-hee (Shin Hyun-been) that what she has found outside the infected building will carry more credibility if she announces it herself to the public, though this way of communicating immediately faces the criticism that it places excessive responsibility on the scientist. Even after she finds her inference proves wrong, the officials hold to it, falling into confirmation bias, and refusing to hear the truth of the incident, which resonates with the way no one listened to Yong-chul’s father when he insisted on his innocence. The conflict between the scientist and the official may look like a cliché at the level of character, but as it displays the very failure of communication Yong-chul describes, it carries the question he raises through to the climax. Director Yeon does not, however, let Yong-chul’s mode of communication encroach on the world. The colony crisis closes at the moment when the two scientists, Se-jeong and Seol-hee, reach an understanding on the phone on the basis of mutual trust, and that ending offers some hope for a system of communication grounded in trust.

Overall, Colony not only plays to Yeon’s strength in making a zombie apocalypse film but also takes up the difficulty of communication at the level of the social system. Yeon’s narrative weakens the characters to some degree, but the new premise it brings to the zombie genre lets the film move past action and raise a question about how communication works among us. It is worth looking back on the present condition, in which AI translates every language instantly and makes communication feel closer than before while the information on social media, much of it false, is repeated until it settles into our perception. Are we communicating with one another in any real sense? Or are we coming to resemble the colony, trusting whatever information is handed to us as our own communicative intelligence decays? Colony turns these questions on a society where communication has never been, where we give less and less thought to what communication itself requires, trust.