AllMovie

A desperate pharmaceutical salesman races to save his family from a parasite that causes its hosts to commit suicide by drowning in this thriller from Big Bank director Park Jeong-Woo. Shocked by the sudden appearance of waterlogged corpses on the banks of the Han River, scientists discover that the deceased have all been infected with a hairworm that compels them to leap to a watery death. As word of the parasite spreads, pharmaceutical salesman Jae-hyuk discovers to his horror that his entire family has been infected. Now, as the scourge surges to epidemic levels and the government sets up a camp for the infected, Jae-hyuk attempts to safeguard his loves long enough for scientists to find a cure.