Season seven is split into two parts that bids farewell to fan favorites Amy and Rory before introducing the (initially) mysterious Clara. In theory, it seems like a fine way to bridge the Doctor ...

Doctor Who, of course, has history with this: Clara Oswald arrived 'early' before getting official companion status, while Peter Capaldi showed up in ‘The Fires of Pompeii’ as Lucius Caecilius ...