Asuka is an outcast in his class. Because of her modesty and inability to find a common language with people, she is the object of mockery and ridicule. The whole class goes on a trip to Korea, and the girl sends them a photo that they have to either forward to another person or die. This is what the inscription on the picture says. Children quickly learn that this is not just a joke and begin a desperate fight for their lives against evil that pronounces a terrible sentence to them.