When the Duke de Richleau and Rex van Ryn sat at dinner that night, there was only one topic of conversation: what lay behind the disappearance of Simon Aron from his usual haunts? The answer was more terrible than they feared. Their oldest and dearest friend had fallen prey to Satanism the deadliest enemy of mankind. If de Richleau and Rex were to save him, they had first to conquer the Forces of Darkness. And that meant treading the most perilous path of all...