The last thing bookworm Frederick Platt wants in his cloistered, little life is to explore a dirty, nasty cave. A glass of warm milk and a good book at home is more his style. But when vengeance turns the tables, Frederick wakes, bruised and battered at the bottom of a dark pit, with only a flickering flashlight for company. Surrounded by his worst phobias and with cold and starvation gnawing at his heels, Frederick struggles to survive deep in the belly of the earth. To find his way back to the light, he will have to conquer his fears and ultimately, himself.