Doctor Who -- The Reason

I was introduced to Doctor Who only a few months ago. A friend recommended the series to me and something about the concept intrigued me, so on a lark I decided to buy the first season (2005).
After watching the first episode with Chris Eccleston and Billie Piper I was hooked. Soon my night was not complete without watching at least one episode of Doctor Who. I have tried to dissect in my mind why I love this show so much. I can't quite put my finger on it but because I'm a writer, I feel I have to try and define what makes this ongoing story great. And so I shall review each episode in order to try and see why this show has such a grip on my imagination. I will link each review at the end of the episode so that there are no spoilers.
Please join me in a discussion of the enigmatic lure of Doctor Who.