Young Will Vandolah spends the summer of 2067 A.D. serving on an Archaeological reconnaissance team that discovers a mysterious treasure hidden in a cave on a small Mediterranean island. A vault of clay tablets inscribed with ancient cuneiform writing hold a mystery that will not reveal itself to him.
A decade later Will is working under his mother's wing on the newly established Titan base, orbiting Saturn. However, the greenhouse they live in is dying. Oxygen deprivation is slowly throwing the crew into delirium. As the crew races against time to solve their problems, Will discovers a new and far worse threat. An enormous comet hurtling through space passes close to Saturn and triggers a chain of events that detonates the rings into a glowing inferno, blasting deadly radiation into space.
Then, another problem is uncovered: the radiation is reaching Earth, causing apocalyptic disaster. Will traces the comet's orbital period and finds the date of its last passage was familiar . . . a date he had seen somewhere before. The date matched the numbers inscribed on the door to the mystical cuneiform vault!