Apparently it has been 12 years since Buffy the Vampire Slayer aired its last episode, which seems a remarkably long time. That's because it remains so vividly not only in my memory, but in pop-culture and TV discussions. Joss Whedon may now be directing billion dollar blockbusters, but this show was his first major breakthrough as the creator of his own wold, and stands among the best work he has ever done. It gave us a really strong female lead, brought vampires back to the mainstream, and blended some great action with heart and whip-smart Whedon dialogue that many have tried to replicate since. Given that it existed from 1997-2003, it means that Buffy was around before the internet really grew to what it is today, and before shows like Lost took fan-investment and online theorising to a whole other level. Despite that, it has a loyal fanbase who have taken the discussion of the show beyond its end, helped by the fact that it still exists thanks to some canonical comics. A number of fan theories for the show do exist, and, well, they're all a little bit crazy. From cheese metaphors to one big, interconnected universe, via Doctor Who, these are the most outrageous fan theories for Buffy.