Sang-hyun is always struggling from debt, and Dong-soo works at a baby box facility. On a rainy night, they steal the baby Woo-sung, who was left in the baby box, to sell him at a good price. Meanwhile, detectives were watching, and they quietly track them down to capture the crucial evidence.
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.
A retired contract killer goes on a bloody rampage when a young girl finds herself at the mercy of gangland human traffickers and only one man can come to her rescue, with an arsenal of weapons and years of experience in the art of killing.
