What starts out to be a normal visit to a cave, becomes a frightful experience for Billy John, Jeanne, Mike and Skylar. Traveling from New York to Kentucky, the couples are excited at the thought of exploring what is known as the longest cave in the world Ambrose Fuller, a psychopath and murderer, follows the four to the cave in search of Jeanne, whom he is strangely attracted to. The kidnapping was supposed to be a joke played on Skylar who thought it funny to mock Billy John's southern accent. A frustrated Billy John comes up with a scheme to scare Skylar for what he feels is her insensitivity towards him. But the joke goes awry when two unscrupulous armed men get in on the act and actually kidnap Skylar for ransom. From that point on, nothing seems to go right for Billy John, Jeanne, and Mike as they make their way through the gigantic, sometimes dangerously dark, and foreboding cave, hoping to find Skylar before it's too late