This is the third (third? I think) Doctor. This is the first time I have watched episodes with Jon Pertwee. At the end of War Games, the Doctor was exiled to earth. This episode starts with the TARDIS materializing and the Doctor falls out and passes out. There is also an alien invasion going on, which gets the Brigadier and UNIT involved. He doesn’t recognize the Doctor at first since he has a different face but since the Brigadier has met the Doctor before, that isn’t much of a problem. Liz Shaw doesn’t like working with UNIT but the Doctor charms her, Jon Pertwee is a very charming Doctor, even when he tries to escape, he hangs his head and apologizes and is forgiven.
In the end, the Doctor and Liz figure out how to kill the Nestenes and the Doctor strikes up a deal with the Brigadier for laboratory supplies, clothes and a car. After all the Doctor is stuck on earth for the foreseeable future.
The problem with watching the old episodes is a lot are missing. So that means a lot of jumping around. The advantage of watching them on DVD is I get to watch the whole story-line at once, even if it stretches out to 5 or 6 episodes. Also, I watch the DVDs in the order I get them from the library, and since some are there and some have to be requested, I am not always watching them in order.