Strella

Princess Strella of Tara was taken prisoner by Count Grendel of Gracht. He intended to use her to gain a place on the throne. She was identical in appearance to Romana who, along with the Fourth Doctor, freed her. The android replica of Strella created by Grendel announced her full title as "Princess Strella, descendant of the Royal Kings of Tara, Mistress of the domains of Thorvald, Mortgarde and Freya". (TV: The Androids of Tara)

Behind the scenes

 * Mary Tamm, who played Strella also played Romana in The Androids of Tara, as well as the rest of Season 16.