A man of science and liberal thought — quite literally a "Renaissance man" — he was naturally inclined to trust the Fourth Doctor despite Federico's attempts to label the Doctor as a "spy" and a "sorcerer". The two struck up a friendship once the Doctor began to apply scientific reason to explain the mystery of guards whose bodies had been desiccated by the Mandragora Helix. This bond was strengthened further when the Doctor joined Giuliano in an out-numbered sword fight against Federico's men.