Doctor Who: 10 Things You Never Knew About The Day Of The Doctor

2. A New Doctor Before His Premiere Episode

By November 2013, it had already been announced that Matt Smith was leaving at the end of the year, and Peter Capaldi was cast as the Twelfth Doctor. Fans were disappointed to have to say goodbye to the Eleventh Doctor, but at the same time there was a good deal of anticipation for his upcoming regeneration, and most people were looking forward to the first scenes of Peter Capaldi as the Doctor in the Christmas special. To the astonishment and shock of everyone, though, the Twelfth Doctor made his debut in The Day of the Doctor - not through a regeneration, mind, but in a tantalising glimpse into the Doctor's future. The Doctor had summoned all of his past selves to Gallifrey in an effort to save it from its ultimate destruction, but to everyone's surprise, his future self arrived, too. It makes sense if you think about it. This was the Doctor's future self, which meant that he remembered sending out the summons, and he may even have remembered seeing himself there. It was an unexpected appearance, nonetheless, and made a perfect moment in Doctor Who history even better. And speaking of future selves...