Film student Jay is currently planning his graduation film, which follows a simple premise: he films himself and his friends, who are hiding something from him, on a boat trip. He wants the truth to come out and the camera to capture it all. The trip leads the group into a tunnel shrouded in mystery, from which there is suddenly no escape and where things are clearly not right. And it soon becomes clear that anyone who speaks the untruth will feel the tunnel's fury.