“In much wisdom there is much sorrow” is a phrase from Ecclesiastes that is true at all times. But there is also such wisdom, the owner of which, in addition to sadness, exposes his life to mortal danger. XVI century, Italy. Disgraced scientist and astrologer Lucio Constantini becomes the owner of an ancient Arabic manuscript containing a secret that could shake the foundations of Christian civilization. The secret brotherhood, the Order of the Good of the Lord, trying to prevent the penetration of dangerous knowledge into the world, does not disdain by any means. For all means are good in the name of a holy cause - from betrayal to a dagger in the heart.