Doctor Who: The Tenth Planet (1966) written by Kit Pedler and Gerry Davis, directed by Derek Martinus
The First Doctor (William Hartnell) has his swan song when the TARDIS lands at the Earth's south pole in 1986 (which was twenty years in the future from the original broadcast date; now it is over thirty years ago!). He and companions Polly (Anneke Wills) and Ben (Michael Craze) arrive at a base directing various space ships. Things go haywire when a new planet shows up, coming toward the Earth. The new planet is absorbing energy from the Earth (and the space ships). If that wasn't bad enough, a ship from the new planet lands by the base and the aliens who come out are Cybermen (in their very first appearance).
The story has a lot of fairly convincing science (writer Kit Pedler was a medical doctor in addition to being a science fiction writer) and impressive looking sets. The "mission control" set has plenty of levels and sciencey equipment. The humans have a hard time getting their space ships back on the Earth; they have a missile that could be used to destroy the other planet, but as usual for Doctor Who, the characters discuss the moral and physical ramifications of using a planet-destroying weapon. Will the earth be in jeopardy too? Can they kill off a whole other race? I found the story quite interesting.
The production did have some challenges. Hartnell collapsed during the second episode, requiring some quick redistribution of his lines while his character recuperated in a different room for a couple of episodes. Hartnell recovered enough to act in the last episode. The end of the episode features the first regeneration of the Doctor (thus the first appearance of Patrick Troughton as the Second Doctor). Unfortunately, the fourth episode was lost in the BBC archives and only bits of it are extant. All the audio was available. This DVD has an animated fourth episode that works to finish the story. It also has a version of the fourth episode that was released on VHS--photos were substituted in for the missing video with subtitles to explain any story details. The reconstruction is less satisfying than the animated version but still interesting.
The Cybermen are great villains--they are basically humans that have taken so many cybernetic attachments that they all they have left are organic brains. Everything else is robotic. In the process, they've shed emotions, living solely by reason (it would be interesting to see a match-up between Cybermen and Vulcans). If the Cybermen are in trouble, it's only logical to take what they need from others, even if that involves the death of others. Their cold-hearted methods makes them unnerving. Their voices have a computer cadence that is also off-putting. Considering other 1960s Doctor Who baddies, the Cybermen costumes are impressive though certainly not as sleek as their 2000s counterparts.