On a dream vacation hiking in the Himalayan Mountains, Charlotte, an overworked broker from Pittsburgh, and her husband Kevin, an archaeologist, are suddenly separated when she mysteriously disappears. She has fallen without a trace through a crack that tunnels deep down into a mountain cavern. Charlotte has to learn to survive in this foreign environment and hopes for rescue while desperately trying to escape. When she discovers an ancient cave painting with a hidden message, she is required to decode it for clues to exit the cave. Kevin, who is still above ground, furiously searches for her with help of rescue crews to no obvious avail. Charlotte battles depression and thoughts of self-harm in the darkness of the cave for an extended period of time. Kevin is a roller-coaster of hope and depression during his searching and vows to not leave the mountains without her. Charlotte uses the message of the cave painting to escape it after being in it a month where God provided for all her needs supernaturally. Kevin is led through many trials during his searches, and when he is at the end of his rope, they are reunited in what some might call coincidence, but is actually all part of God's plan. Charlotte and Kevin come out of this experience changed and their marriage and faith strengthened.