Following an end-of-term school ceremony, the American boy Bobby decides to go with his friend Akkun into the mountains outside their village, to a place perfect for a secret base. On the way they stop into a mysterious amusement park. They have fun there, but are attacked and cannot leave. Falling in with some other children who are also lost there, they fend off a number of attacks, and gradually learn the truth behind the facility. It was put there by a man named Koike as a trap for passing children. His son Takashi needs to feed on human children in order to survive. Akkun is killed, and Bobby is captured with Tokiko, a girl they have met there. She disappears, and Koike goes to work on Bobby, trying to fatten him up. Bobby manages to escape. With the help of Saruyoshi, a mysterious old hermit, and the animals of the forest, Bobby builds up his strength and returns to the facility in an attempt to save Tokiko.——IMDb
What begins as an annual visit to their family grave-site quickly becomes a night of sheer terror as two brothers are unexpectedly forced to fight back against a sudden onslaught of violent assailants. Soon, eight complete strangers find themselves barricaded inside a rural farmhouse in an attempt to survive against the ever-growing army of murderous creatures outside.
