Synopsis: As it has done for ages, the Han River continues to pierce the very center of the capital city Seoul. But one day in the year 2000, through an unfortunate incident, a creature of an obscure nature is conceived in the waters of the river. As the creature slowly starts to grow in the depths of the river, people fail to sense signs of an impending disaster, devoting themselves to the Korea-Japan World Cup soccer finals, the Presidential elections and to their individual lives. Then, one day in 2005, in front of countless citizens taking a stroll and enjoying the weekend on the banks of the Han River, the creature reveals itself in a shocking display of horror and mass slaughter. In an instant, the riverbank is turned into a gruesome sea of blood. The main character Gang Du is a man who passes tedious days operating a snack bar next to the river. On that day of great destruction, he witnesses his one and only daughter eaten up by the creature right before his eyes. The sudden appearance unforeseen and unexpected circumstances render the government and state powerless to act. And the once-ordinary citizen Gang Du and his family are thrust into a battle with the monster to rescue Hyun Seo. On the banks of the river, which are completely closed off by the government and declared a danger zone, Gang Du and his family rush into an unstoppable showdown with the monster.