影音先锋Peter Capaldi’s final episode of Doctor Who this Christmas will feature Pearl Mackie as Bill Potts and be called Twice Upon a Time，it was revealed this evening（23 July）during a cast panel at San Diego Comic Con. Viewers will have to wait until Christmas to discover exactly how Bill，who will appear throughout the episode，makes her return.神秘博士:2017圣诞特别篇影音先锋http://www.xianfenglunli.com/lunli/106914.html