Dawn Summers, that is. So, as you may or may not know, I have been watching a lot of Buffy. But that's not the point, so you can mock me in the comments. Starting now.

One of the characters thrown into the mix mid-series is Buffy's younger sister, Dawn. The character is one of the most interesting ever introduced into any show. The idea is that she The Key that unlocks dimensional barriers. Big Whoop. What's interesting is how she was introduced to the show. The Key was originally protected by monks until they turned it into human form and put it under the watch of the slayer. So the monks gave her a memory and changed Buffy's and her mother's as well. Here's comes the interesting part.

This is essentially what every writer does in every piece of fiction. They create memories and bonds and birthdays. The writers were able to have Dawn become a member of the cast without having to slowly weave her into the story. If you had started watching the show the week after Dawn was introduced, you wouldn't have known that she hadn't been around the whole. It is a truly ingenious writing tactic. I wouldn't be surprised if this had been done in a soap opera some time ago, but it still a great idea.