Leonardo da Vinci's final painting, Saint John the Baptist, has baffled art historians for centuries. At first glance, it is a devotional portrait of a beloved Catholic saint. Yet its provocative depiction defies convention, eluding all attempts at interpretation--until now. Through meticulous research spanning centuries, a groundbreaking discovery unveils the painting's hidden meaning. From the baptism of Christ and the suppressed Gnostic Gospels to its reverberations in modern times, this enigmatic work redefines our understanding of art, history, and power. Holy Ghost is the gripping true story behind da Vinci's most mysterious masterpiece.