Sarah is used to lure The Doctor into a trap, the village sleeps while The Zygons begin their plan for a takeover of the Earth.
When you look at the names associated with this, Robert Banks Stewart, Douglas Camfield and Robert Holmes, is it any wonder it turned out so good? Direction and production are superb, it looks wonderful, I love the appearance of the Zygons, way better than the new ones. The sets are wonderful also.
Tom is incredible, at the very top of his game, he's sincere, strong, and as I watch this, I firmly believe in his Timelord character, he uses his wonderful eccentric personality to make The Doctor alien. It's a great episode for Harry and Sarah, Sarah finally does some journalism, and Marter gets to play an evil Harry, brilliantly. Banks Stewart seemed to write each character very successfully, every detail about them was considered.
Once again, I can find no fault, the story has progressed so well. Loving it. 10/10