Number Two, or Pencilla, is Mr. Benedict's secretary and first adopted daughter. She is often portrayed as having a rather mouse-like character. Number Two very rarely sleeps, so food is her only source of energy. If she fails to consume enough food, she tends to get nervous and irritable. Her sleeplessness proves very useful on more than one occasion. For example, she manages to get a tremendous amount of work done on the eve of the Society's trip to the Institute, and in The Perilous Journey, her restlessness allows her to get the pin in her cuffs unlocked, and thus allowing her to escape. Her real name was not revealed until the end of The Prisoner's Dilemma, when Constance tricked her into thinking it, and plucked it from her mind.