3) The 10th Anniversary
The first big one, and one with a lot of important history-making moments for the show: we got “The Three Doctors,” the very first multi-Doctor story; we got the introduction of Omega—who, while not being on the level of villains like the Daleks or the Cybermen, is still one of the show’s most iconic big bads; and, on a more somber note, we got William Hartnell in action as the first Doctor for the very last time. “The Three Doctors” isn’t just a moment in time though, it’s still a great adventure with a lot of meaning for the show.
