The Book of Q — Jonathan Rabb

After the mysterious death of one Vatican priest and the disappearance of another, Father Ian Pearse, an American working on ancient Christian texts in the Vatican, comes into possession of a mysterious scroll. He discovers ingeniously coded letters and the text of an ancient Manichean prayer that has never before been found in written form. These reveal a Manichean conspiracy - a sect long-thought dead - reaching deep into the present Vatican hierarchy. Racing from the Vatican via an ancient Greek monastery to war-torn Bosnia, Father Pearse has to decipher the cryptograms and codes before the closely guarded heresy is unleashed on the world.