Tom (played by Keith Durham) was the father of Guinevere. He worked as a blacksmith in Camelot. When Nimueh poisoned the city's water supply, he fell victim to the magical plague which had killed many others. Merlin cured him using magic, resulting in Gwen being blamed for causing the plague. She was arrested for witchcraft but later released, and joyfully reunited with her father. Tom made the sword which became Excalibur when the Great Dragon gave it magical powers for Arthur's use. He later became involved in a plot by a sorcerer, Tauren, to perform alchemy using the legendary Philosopher's Stone (referred to in dialogue as the "maidstone"). Tom was arrested and put on trial for treason in unwittingly assisting a known enemy of Camelot, because Uther believed that Tom was supplying weapons to Tauren. Morgana suspected that the trial was a formality and Uther planned to have Tom executed anyway just to make an example of him. He was then killed by soldiers after she helped him to escape from the dungeons.