The BBC have confirmed that episode eight of Series 9 and part two of two, The Zygon Inversion, will air on Saturday 7th November at 8pm.
The episode will last for 50 minutes, and finishes at 8.50pm. The Zygon Inversion, co-written by Peter Harness and Steven Moffat, will air on the same day on BBC America at 9/8C.
Shapeshifting Zygons are everywhere in the UK, and there is no way of knowing who to trust. With UNIT neutralised, only the Doctor stands in their way. But how do you stop a war? And what can the Doctor do to save his friends?