Andreas, nephew of the abbot of the Monastery of Dionysios, who died eight years previously, arrives at Agion Oros (Mount Athos) with a team of smugglers of antiquities, with the intention of stealing a gold cross set with precious gems, known as the Cross of Alexander the Great. He earns the trust of the meek and hospitable monks. However, a Jewish girl, Anna - whom, while still a baby during the war, her father had entrusted to the care of the hermit Vasileios - continues to pretend she is a young monk. She manages gradually to discover the entire scheme and acts to foil their plot. With dogged persistence, she persuades Andreas to repent, and together they rescue the valuable relic and smash the band of thieves.