In the winter of 1271, the mortal remains of Luis IX, the Holy King, are carried across the Italian peninsula by his retiring army. The seventh Crusade, which aimed at converting and defeat Tunis, has badly failed.
During this sad long funeral, five knights meet in circumstances too difficult to explain rationally. All five of them share the same secret: the knowledge of the place where the Sacred Shroud is kept, hidden by some traitors of the French court. Therefore, they leave on a journey rich in amazing adventures, from the Apennines between Tuscany and Emilia all the way to Otranto, then across the sea to Tebe, in Greece, where the most sacred relic is hidden. The five knights will succeed in taking the Sheet in which Christ was laid after Crucifixion, stained with His blood. They will succeed also in the not so easy task to take it back to France and hand it over to a member of the royal family.
However, a totally unexpected destiny awaits them.