Terror of the Zygons (airdate December 25, 1983)
Intro: [beginning clipped on available copy] lot-- ugly, evil-tempered, and clever. If they were to ask Santa for a Christmas gift, it would probably be a huge monster, capable of delivering death and destruction in copious quantity. But of course, they wouldn't ask Santa in the first place. And the right jolly old elf certainly wouldn't honor such a request. The thing just wouldn't fit in his sleigh. Unfortunately for the Doctor and friends, the Zygons seem to have obtained one somewhere else.
"Next Week": Next week, the Doctor and Sarah will head back to London from Loch Ness. But fate has a much longer journey planned for the TARDIS... all the way to Zeta Minor, a planet on the outermost edge of the known universe. What will they find there? That is a matter... or should I say anti-matterto be discovered next Sunday night at 11, on... the "Planet of Evil."