Elizabeth X, a.k.a. 'Liz 10', reigns as Queen of England In Space. While having a youthful appearance, she is nevertheless of extraordinary age, having had her clock stopped for the sake of successional stability during the period of Britain's enforced exile from Earth. Clock-stopping causes her to age with extraordinary slowness. For much of that time, she is unaware of her great age due to periodic self-induced memory wipes ( The Beast Below ).At some much later date (evidenced by visible gray streaks in Liz 10's hair) ( The Pandorica Opens ), she apprehends River Song in the act of stealing a Van Gogh painting from the National Gallery.