Doctor Who Extra: The Zygon Invasion By TGT | 1st November 2015 The BBC have released a few behind the scenes videos from last night’s episode, The Zygon Invasion, which you can watch below: Share this:Click to share on Facebook (Opens in new window)Click to share on Twitter (Opens in new window)Click to share on WhatsApp (Opens in new window)Click to share on LinkedIn (Opens in new window)Click to share on Reddit (Opens in new window) Related Posted in News and tagged Behind The Scenes, Doctor Who Extra, The Zygon Invasion