10 Changes Doctor Who Hoped You Wouldn't Notice

The UNIT Dating Controversy is one of the longest-running debates in the history of the show, stemming from some continuity issues introduced during the classic era.

It's a huge problem with many details to consider, but the basic issue is that - when you take into account several dates given during classic serials - the timeline of UNIT doesn't make a lick of sense.

The main example most fans will point to is the Second Doctor serial The Invasion, which first introduces UNIT, and ostensibly takes place in 1979. Nothing wrong there. But then, in the Fifth Doctor serial Mawdryn Undead, the timeline of UNIT is completely changed.

Here, Brigadier Lethbridge-Stewart says that he retired from UNIT "seven years ago", which would mean that he left in 1976. This then begs the question: how could the Brigadier retire from UNIT before UNIT even existed?

Obviously, the writers of the show weren't intending to cause mass fan hysteria by simply changing a few dates and inadvertently screwing up the timeline, and in all likelihood, they probably thought that nobody would care too deeply.

And while some people really do care, at the end of the day, this is just a fun quirk of the show, one that doesn't remotely detract from the quality of the stories.