Gaius is the royal physican at the court of king Uther Pendragon of Camelot. Gaius is wise and erudite, even versed in magic, but dreads using any as the king has banned 'sorcery' on pain of death. Nevertheless Gaius generously accepts Merlin's mothers plea to take the boy on as his medical apprentice, and a soon as he discovers Merlin's natural magical aptitude decides to coach him both careful discretion and secret study, even gives him a priceless magic handbook. Even when prince Arthur makes Merlin his squire, gaius remains his mentor and medical teacher.