Marine Captain Jung-seok drives past a family pleading for help while escorting his own elder sister, her husband Chul-min and son Dong-hwan to a ship leaving South Korea. Once aboard, Jung-seok learns the ship is now being taken to Hong Kong. Before he can do anything, the zombie outbreak sweeps those aboard, including his sister and nephew. Jung-seok and Chul-min survive and settle in Hong Kong. Four years after the apocalypse, the two are sent along with two others Koreans to the peninsula on a mission to retrieve a truck full of money. They're promised half of the share if they make it alive along with the truck, but Jung-seok is initially reluctant. Seeing how this is affecting his relation with Chul-min, he agrees to go along. Once they land in the peninsula, they search for the truck and find it. Soon, zombies start chasing them but they manage to escape with the truck unharmed. However, on their way back to the Incheon port, the team is ambushed by a rogue militia group named Unit 631, led by Sergeant first class Hwang. Jung-seok is thrown out of the truck while Chul-min hides inside it. The female Korean dies. As zombies start chasing Jung-seok, he is cornered but rescued by two young sisters Joon and Yu-jin who leave the zombies behind, following a car chase. At their hideout, Jung-seok meets their grandfather Elder Kim and mother Min-jung. Jung-seok instantly realizes it was Min-jung he drove past while saving his own family.The truck is seized by Unit 631 after Hwang kills the remaining Korean who's slowly transforming. Chul-min is found inside the truck and in spite of his requests to set him free, is captured and thrust into fighting zombies along with other captured men in a gladiator-style game. On the other hand, Private Kim and Captain Seo subsequently discover the bags of cash in the truck and conspire to escape together, leaving behind Hwang and his team. Meanwhile, Min-jung learns of a ship at the Incheon port waiting to extract Jung-seok, and decides to steal the truck so that the five of them can escape. They arrive at Unit 631's compound, where Jung-seok and Min-jung neak sneak inside as the sisters and the old man wait for them in the car. The two discover the truck and encounter Private Kim. Jung-seok finds out that Chul-min is alive inside the compound and goes to rescue him. He ends up killing a number of zombies and Unit 631 soldiers, before Chul-min is shot dead by Hwang. Min helps Jung-seok escape by driving the truck away from the compound. They're joined by the sisters as they engage in a car chase with the zombies and Unit 631. The prolonged car chase results in Hwang and his driver getting killed.As the five reached the port, an injured Seo rams his car into Joon's car and takes her hostage. Elder Kim is shot while protecting Yu-jin and Min-jung is shot in the leg by Seo. Jung-seok tries to capture Seo but in vain as the latter escapes with the truck and boards the ship. However, he is shot inside the ship and before dying, reverses the truck to prevent the ship's gate from closing, eventually allowing zombies to enter and kill everyone inside. The grieving four then spot a United Nations military transport helicopter and direct it to land on the port. Min-jung, who made Jung-seok promise a favor to her in return for her daughters saving him, tells him to be with the girls at all costs. Jung-seok agrees and runs to the helicopter as Min-jung provides cover. In the process, she finds herself inside a car surrounded by zombies. Before she can kill herself, Jung-seok recalls Chul-min's earlier claim that Jung-seok didn't do his best to save their family, eventually rescuing Min-jung by killing the zombies around her. The four then board the helicopter and escape the peninsula.