10 Buffy The Vampire Slayer Episodes That Changed Everything

4. Buffy Vs. Dracula

Retconning (basically the process of changing the established history of a work of fiction) is a familiar term in the comic book world, but in television circles, it wasn't normally done - at least not until Buffy was given a sister who was treated as if she had been on the show all along, despite only turning up in the fifth season. Fans were left in the dark as to who Dawn was (other than Buffy's sister) and just why she was there, with no explanation immediately given. It was simply presented as established fact: Buffy had a sister. Buffy vs. Dracula marks her first appearance, though the season's second episode is her real introduction. Either way, it was an addition that really did change everything, and moving forward, shows were much more willing to take risks with continuity (Fringe being a great example).