<P> The episode was the official beginning for Clara Oswald, but Coleman had appeared twice before, as two different characters . </P> <P> The Great Intelligence makes its second appearance in a row after appearing in the preceding episode, "The Snowmen". In the intervening time, the Great Intelligence has encountered the Doctor's second incarnation twice, once in the Himalayan mountains during the 1930s and once in the London Underground in the 1970s . </P> <P> The woman in the shop who gave Clara the Doctor's number is brought up in "Deep Breath". The Twelfth Doctor remarks it seems as if someone is trying to bring the Doctor and Clara together . The episode "Death in Heaven" reveals it was the Master (as Missy) who gave the number to Clara . </P> <P> Writer Steven Moffat described the premise as </P>

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