After hearing a young boy’s cry for help, a sister and brother venture into a vast field of tall grass in Kansas but soon discover there may be no way out…and that something evil lurks within. When siblings Becky and Cal hear the cries of a young boy lost within a field of tall grass, they venture in to rescue him, only to become ensnared themselves by a sinister force that quickly disorients and separates them. Cut off from the world and unable to escape the field’s tightening grip, they soon discover that the only thing worse than getting lost is being found. While traveling to San Diego, Cal DeMuth stops the car nearby a tall grass field since his pregnant sister Becky is sick and need to vomit. They overhear the cry for help from a young boy and decide to look for the boy in the field. Soon they realize the field is a supernatural place that manipulates time and space and there is no way out from the tall grass.