The BBC have revealed the synopsis for episode 7 of Series 9 - "The Zygon Invasion" - which will air on BBC1 on Saturday 31 October 2015 at a time yet to be confirmed:
The Zygons, a race of shapeshifting aliens, have been living in secret among us on Earth, unknown and unseen - until now!
When Osgood is kidnapped by a rogue gang of Zygons, the Doctor, Clara and UNIT must scatter across the world in a bid to set her free. But will they reach her in time, and can they stop an uprising before it’s too late?
Writer/ Peter HarnessNow, THIS is the two-parter I've really been looking forward to - Zygons...the return of Kate Stewart and UNIT ... what's not to love?
Director/ Daniel Nettheim
Producer/ Peter Bennett