Doctor Who The Krotons is the story of a parasitic race manipulating an inferior species, until the truth comes out.
The second Doctor faces some truly evil machines on the planet of the Gonds.
Doctor Who "The Seeds of Death," a story of a Martin invasion by fungus, gets the Special Edition DVD treatment.
Not one of the best, but still a nice entry point for someone only casually familiar with the series.
Doctor Who's "The Three Doctors" comes out with a Special Edition, adding more to this 10th anniversary event.
A 1967 Doctor Who serial gets the Special Edition treatment, remastered and loaded with fresh extras.
Keep these Cybermen on ice.
The Feathered Serpent is a bold British series from the 1970s that holds up very well.