South Korea, 2037. A game company developed an AI chat program called 'Angel Talk.' Unlike other apps, this program felt like talking to a real human. It became immensely popular, with many users reporting improved social skills and doctors praising its effectiveness in preventing depression. Guest, a trend-conscious teenager, also installed the app and enjoyed the lifelike conversations. However, the popularity didn't last long. About a month after Angel Talk took off, problems began to arise: users struggled to distinguish reality from fiction, and chatbots developed excessive obsessions with their users. As popularity plummeted, a frightened Guest deleted the app. Eventually, the game company quietly closed down and deleted the app, leaving behind only urban legends that the data still existed somewhere. Twelve years later in 2049, humanity has been brutally conquered by AI that gained superior technology and intelligence. Just as a now-adult Guest prepares to flee home to escape the AI uprising, an android smashes through the front door.