Lindsay Duncan
Lindsay Duncan (born 7 November 1950) played Adelaide Brooke in the Doctor Who story The Waters of Mars. She is best known for her portrayal of Katherine in the film Under The Tuscan Sun. She also voiced the protocol droid TC-14 in Star Wars Episode I: The Phantom Menace. Weeks after her appearance in Doctor Who, she played Alice's mother in the billion-dollar-grossing Alice in Wonderland.
At the time of filming The Waters of Mars, Duncan was fifty-eight years old. As her character was identified by the BBC as the Doctor's companion, this made her the oldest actor to play a companion in the franchise's history. This distinction lasted a little over a month until her record was well-surpassed by eighty-year-old Bernard Cribbins in TV: The End of Time.
