The city of Hwayang is a suburb near the capital. An unknown infectious disease breaks out from the city that houses 290,000 people. The first to get sick is a middle aged man who used to breed dogs. The man had contracted the new flu, and after getting bit by a sick dog, his eyes swell up red and he starts to bleed from his entire body, including his lungs. The disease starts to spread from the 119 emergency response workers that were deployed to save him. In an instant, the emergency doctors and nurses' eyes turn red, and suddenly die in a few days. Soojin, a nurse in ER, and Kijoon, a fireman, starts to understand the severity of the situation ...