When his brother is mysteriously saved from drowning, Frederico is inspired to research his Quinta's history and discovers a celtic sanctuary donated to the Cistercians by Portugal's first king Afonso Henriques. The truth behind folklore of a treasure trove hidden in this Royal Forest near the Knights Templar port of Atouguia slowly dawns. In the visigothic chapel, a fresco painting showing Our Lady with a beard holds the key to the great secret of the Knights Templar: the Holy Grail!