F is for... Federico, Count

Count Federico was the brother of the Duke of San Martino, and uncle to the heir Giuliano. He coveted the dukedom for himself, and so employed the court astrologer Hieronymous to first predict the old Duke's death, and then to have him poisoned. Whilst his brother lay on his death bed, Federico and his henchman Rossini went out to bully and terrorise the local peasants - which Giuliano considered his brutish uncle's idea of sport. When the Doctor arrived in the town, in search of a fragment of Mandragora Helix energy which had stowed away on the TARDIS, he was captured by Rossini and brought before the Count. Federico accused him of being a spy and ordered his execution, after dismissing his warnings.
The Doctor escaped, but Federico then ordered Hieronymous to forecast - and bring about - Giuliano's demise. He wanted the young man dead before his accession to the Dukedom, as he had invited many influential guests to the ceremony, and he did not want him to establish himself. When the astrologer refused to obey him, he ordered his capture and death, little knowing that Hieronymous was the leader of the pagan Cult of Demnos, and had been taken over by the Mandragora Helix.
The Doctor finally convinced the Count to accompany him to the Cult's underground temple to witness for himself what was going on. When Federico attempted to challenge Hieronymous, he found that he was now pure Mandragora energy. Hieronymous struck him down with a lethal energy bolt.

Played by: John Laurimore. Appearances: The Masque of Mandragora (1976).

• Laurimore was a late replacement for the role, as actor David Swift (of Drop The Dead Donkey fame) had already been cast but had to withdraw a few weeks before location filming began.