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 throuh 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 President elections and to their lives. Then one day in 2005, in front of countless citizens taking a stroll, 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 fateful day, he witnesses his only daughter swallowed up by the creature right before his eyes. This strange occurrence and unexpected circumstances renders the government and state powerless to act. 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 a nail biting series of events and a showdown with the monster.

As opposed to a belligerent, city thrashing giant, the monster in the Host is a giant mutated fish about the size and proportions of a T-rex. The special effects used to bring the creature to life are remarkably convincing.

On its face, The Host is your basic environmental allegory; the abuse of nature, in this case pollution (by callous American scientists who dump a crate’s worth of “dirty” formaldehyde down the drain and into Korea’s Han River), leads to the creation of the monster (the host) who wreaks its vengeance on humanity.

The film introduces us to an unlikely group of protagonists, an inept and lazy man, his morose father and his young daughter. When the creature first attacks the city, the daughter is carried away. Grieving for her, father and son are reunited with Kang-ho's other siblings, a sister who is a competitive archer and a brother, college educated but unemployed. This quartet clearly has issues, and Kang-ho feels guilty for what has happened. After being isolated by the military for having been exposed to the creature, Kang-ho becomes convinced his daughter is still alive.

The family bands together and decides to break out and track down the creature's movements in an effort to locate the girl. Equal parts believable family interplay, genuine horror, slapstick, and harrowing moments with surprisingly real consequences, "The Host" is a multilayered film that works on many levels.