Due to sudden deteriorating weather conditions, visibility on the Airport Bridge is severely impaired, leaving people stranded and at risk of the bridge collapsing due to a series of chain collisions and explosions. Amidst the chaos, the canine subjects "Echo" from the military experiment "Project Silence," who were being transported in secret, break free, and all human survivors become targets of relentless attacks. Various individuals find themselves stranded on the Airport Bridge for different reasons - a government official from the presidential office who was seeing off his daughter at the airport; a tow truck driver who was on his way to a multi-collision scene; an elderly couple who were returning from a trip abroad; sisters who missed their flights, and Dr. Yang, the researcher responsible for Project Silence - and a desperate struggle begins for them to escape to safety. In the wake of the worst chain of disasters, an extreme fight for survival begins!