Five years after the end of World War II, Andreas—the nephew of the late abbot of the Monastery of St. Dionysios—and his international antiquity smuggling ring arrive at Mount Athos. Intent on stealing the golden Cross of Constantine the Great, a priceless Byzantine artefact and symbol of all Christianity, Andreas poses as a visitor and gains the trust of the friendly and gullible monks. Before long, the team gets to work, unbeknownst to them, however, that Anna, a young orphaned woman who is under the wing of reclusive Father Vasileios, is on to them. Can Brother Anna help Andreas change his mind and repent before the ancient relic falls into the hands of the unscrupulous thieves?