Six months after the mysterious death of a high school student, a new girl, Chris, transfers to the school. She is grieving the loss of her father and is not eager to make friends, but on her first night at the school, she finds herself in the company of her classmates. One of the girls playfully whistles into an ancient Olmec whistle that Chris has discovered, and the sound is so piercing that it leaves the students deafened. As a result, they are haunted not only by terrifying visions, but also by death itself.