The Silence are a religious order who consider themselves the Sentinels of History. They are led by a race of aliens who can be erased from the memory of anyone who looks upon them.They kidnap Amy Pond and her daughter and are behind the Battle of Demon's Run, which prompts the Doctor to call in numerous favors.They attempt to kill the Doctor to stop a prophesy: On the fields of Trenzalore, at the fall of the eleventh, when no living creature can speak falsely or fail to answer, a Question will be asked, a question that must never, ever be answered.