COLONY: Could a Zombie Outbreak Really Happen? Exploring the Science Behind Korea’s Latest Zombie Thriller

Introduction

What happens when a mysterious infection traps an entire building in Seoul?

That is the terrifying premise of COLONY (2026), a Korean action-thriller directed by Yeon Sang-ho. The film follows survivors trapped inside a skyscraper after an outbreak, while the infected evolve from crawling, animal-like figures into increasingly coordinated predators. A biotech scientist, Kwon Se-jeong, and the other survivors attempt to reach safety as they uncover the truth behind the outbreak. (Korean Film Council, 2026). While COLONY is firmly a work of fiction, its storyline raises an intriguing scientific question:

Could a real pathogen ever cause something resembling a zombie outbreak?

The short answer is not in the way the movie portrays it.

However, several concepts featured in zombie fiction including viral infection, neurological disease, changes in behaviour, viral evolution and transmission are based on real biological phenomena.

🦠 1. Can a Virus Affect the Brain?

The human brain is protected by the blood–brain barrier (BBB), a specialised system that regulates the movement of substances and protects the central nervous system from many potentially harmful agents.

However, some viruses are capable of reaching or affecting the central nervous system (CNS). Recent research shows that neurotropic viruses can enter the CNS through several possible routes, including crossing the blood–brain barrier, entering through the olfactory system or travelling through peripheral nerves (Sun et al., 2024).

Viral infections can also disrupt the blood–brain barrier itself. A 2025 review found that viruses including herpes simplex virus, Japanese encephalitis virus and SARS-CoV-2 can be associated with BBB dysfunction through mechanisms involving direct viral effects, immune responses and systemic inflammation (Boardman et al., 2025).

So, while a virus cannot turn someone into a movie-style zombie, pathogens affecting the brain are very real.

🧠 2. Can Infection Change Human Behaviour?

This is where zombie fiction gets particularly interesting. When infections affect the brain, neurological symptoms can occur. Depending on the pathogen and the area of the nervous system involved, these effects can include confusion, altered consciousness, seizures, movement abnormalities and behavioural changes (Sun et al., 2024).

One of the clearest real world examples is rabies. Rabies is a viral disease that affects the central nervous system. Once neurological disease develops, patients can experience anxiety, confusion, agitation, delirium, hallucinations, abnormal behaviour and other forms of brain dysfunction (CDC, 2026). That might sound surprisingly similar to certain elements of zombie fiction but there is an important difference. Rabies does not create zombies. It causes severe viral encephalitis and neurological dysfunction. The behavioural changes are consequences of disease affecting the nervous system, not evidence of an infectious “zombie transformation.”

🧬 3. What About Rapid Viral Mutation?

COLONY presents an outbreak in which the infected appear to evolve rapidly, becoming increasingly dangerous and coordinated. Viruses can certainly evolve. Viral populations accumulate genetic variation during replication, while natural selection can favour variants with characteristics that improve their ability to survive and transmit. Research into SARS-CoV-2 demonstrated how viral variants can emerge and differ in properties such as transmissibility, immune escape and overall fitness (Markov et al., 2023; Carabelli et al., 2023).

But there is a major difference between viral evolution in reality and rapid transformation in fiction.

A mutation does not automatically make a virus stronger, more transmissible or more dangerous. Viral evolution occurs through a combination of mutation, selection, genetic drift, transmission bottlenecks and other evolutionary processes.

Therefore, a pathogen suddenly developing multiple complex abilities such as dramatically changing human behaviour and producing coordinated infected individuals within a very short period is not supported by current biological evidence.

🧠 4. Could a Virus Create a “Colony” or Hive Mind?

This is perhaps the most fascinating scientific idea in COLONY. The film's infected do not simply behave as isolated individuals. They progressively become coordinated predators, giving the outbreak a collective or “colony-like” quality. But could this happen biologically? Currently, there is no known pathogen capable of connecting human brains into a shared hive mind. Human behaviour emerges from incredibly complex networks involving the brain, peripheral nervous system, sensory input and social interaction. A pathogen may disrupt neural activity, but that is very different from creating a shared information processing system between infected humans.

In other words:

Brain dysfunction? Real. 🧠

Behavioural changes? Real.

A human zombie hive mind? Fiction. 🧟

🔬 5. What Does Science Actually Say?

Let's separate COLONY from real biology.

Concept	Scientific evidence
Viruses can infect humans	✅ Yes
Some viruses can affect the CNS	✅ Yes
Viral infections can disrupt the BBB	✅ Yes
Neurological infections can alter behaviour	✅ Yes
Viruses can mutate and evolve	✅ Yes
Infection can cause agitation or confusion	✅ Yes
A virus can turn humans into undead zombies	❌ No evidence
A virus can create a human hive mind	❌ No known mechanism
Humans rapidly transforming into coordinated predators	❌ Fiction

The interesting part is that COLONY does not need every element of its outbreak to be scientifically realistic. Instead, it takes real biological phenomena and pushes them to an extreme.

🧪 6. Why Zombie Fiction Is Scientifically Interesting

Zombie movies may seem like pure entertainment, but they can provide an interesting way to think about infectious disease. The real world already contains pathogens capable of causing severe neurological disease. Some viruses can reach the CNS, disrupt the blood–brain barrier and trigger inflammation that affects neurological function (Sun et al., 2024; Boardman et al., 2025).

At the same time, viral evolution is a genuine and dynamic process. The COVID-19 pandemic demonstrated how viral populations can change over time, with variants gaining combinations of characteristics that influence transmission and immune escape (Markov et al., 2023; Carabelli et al., 2023). But biology has limits. A virus cannot simply “choose” to become a perfect zombie pathogen. Evolution does not work toward a predetermined goal. Changes that appear in viral populations are shaped by biological constraints and selection pressures.

That distinction between what biology allows and what fiction imagines is what makes COLONY such an interesting movie to analyse.

🧬 Final Verdict: Science or Fiction?

So, could a COLONY-style zombie outbreak really happen?

Not as shown in the movie.

A virus affecting the nervous system? Absolutely possible.

Neurological disease causing behavioural changes? Already documented.

Viral evolution and the emergence of new variants? Definitely real.

A virus turning humans into coordinated undead predators with a shared hive mind?

That remains science fiction.

And perhaps that is exactly what makes COLONY so entertaining.

It takes real concepts from virology, neuroscience, immunology and evolution and asks us to imagine what might happen if those biological processes were pushed far beyond their real world limits.

So next time you watch a zombie movie, don't just ask:

“Could I survive the apocalypse?” 🧟‍♀️

Ask:

“What does biology get right?” 🧬

📚 References

Boardman, S.A., et al. (2025) ‘Viral Infection and the Blood-Brain Barrier: Molecular Research Insights and Therapies’, The Journal of Infectious Diseases, 232(6), pp. 1273–1282.

Carabelli, A.M., Peacock, T.P., Thorne, L.G., et al. (2023) ‘SARS-CoV-2 variant biology: immune escape, transmission and fitness’, Nature Reviews Microbiology, 21, pp. 162–177.

Centers for Disease Control and Prevention (CDC) (2026) ‘Clinical Features of Rabies’. Available at: CDC Rabies Clinical Features (Accessed: 17 August 2026).

Korean Film Council (2026) ‘COLONY’. Available at: Korean Film Council – COLONY (Accessed: 17 August 2026).

Korean Film Council (2026) ‘COLONY – New Films’. Available at: Korean Film Council – COLONY (Accessed: 17 August 2026).

Markov, P.V., Ghafari, M., Beer, M., et al. (2023) ‘The evolution of SARS-CoV-2’, Nature Reviews Microbiology, 21, pp. 361–379.

Sun, M., Manson, M.L., Guo, T., et al. (2024) ‘CNS Viral Infections—What to Consider for Improving Drug Treatment: A Plea for Using Mathematical Modeling Approaches’, CNS Drugs, 38, pp. 349–373.