4. The Enemy of the World
Probably the most unfairly misjudged story in all of Doctor Who and this is for one reason: The one existing episode is by far the weakest. Even gems can have a bit that needs polishing and in this case it's Episode Three. However in the five missing episodes there's Patrick Troughton playing two fantastic characters, a Bond-like plot and a fair few action sequences that seem like they haven't been matched in Doctor Who since. If only more of this story existed, I suspect it would be loved a great deal more.