The Valeyard - Doctor Who

The Valeyard is a fictional character from the long-running British science fiction television series Doctor Who. He appears in the show's twenty-third season, dubbed The Trial of a Time Lord. The season's four serials are interconnected through one overarching plot line in which the Valeyard serves as a court prosecutor in the trial of the Sixth Doctor. Within the series narrative, the Doctor is an alien who hails from a race known as the Time Lords. They travel in time and space in the TARDIS, frequently with companions. At the end of the Doctor's life, the Doctor regenerates, changing their physical appearance and aspects of their personality.