When the abnormal descends into reality, containment is war. In this world, there exist countless unexplained anomalous events. They might be a suddenly appearing door, a creature from another realm, or even a disaster sufficient to destroy a city. To control these dangerous entities, a mysterious organization—the Abnormal Containment Facility—was born. The facility classifies all anomalies and dispatches special operation teams to handle them. What seemed like a routine E-class containment mission unexpectedly led operation captain Lin Ye to discover a mysterious portal leading to the demon world. Behind the door lies a terrifying place known as the abyss.