It is 70 AD. A group of Roman soldiers crossing the Sahara desert is destroyed by a ferocious and mysterious presence hidden in a solitary tower at the extreme borders of the sea of sand. The sole survivor, the Etruscan seer Avile Vipinas, is inexplicably saved by the sound of his silver sistrum. Nineteen centuries later, young American scholar Philip Garrett is investigating his father's disappearance in the desert 10 years earlier when he discovers the house of Avile Vipinas in the underground ruins of Pompeii, sealed by the earthquake of 79 AD. The ancient seer, before his death, had tried to describe the horrific presence in the Tower of Solitude and to make the first faltering steps to its destruction ... Who is the ancient civilization - older than the oldest known - that created this tower? What is its purpose?