Over seven days, I am watching and reflecting on one Doctor Who story from the revived series.
Silence in the Library ・Forest of the Dead
By Steven Moffatt
A library that encompasses an entire planet. It’s deserted. Millions are saved, but there are no survivors. A mysterious woman seems to know The Doctor very intimately, yet he has never met her before. Her name is River Song, and she carries a diary, which she says The Doctor forbade her to ever allow him to look at. Stay out of the shadows; or you’ll be eaten.
In this, yet another story by Stephen Moffat (it seems Moffat is the writer of most of my favourite episodes so far, doesn’t it?), we are introduced to a new character: River Song (played by Alex Kingston, of ER fame). The Doctor knows nothing about her, as he’s never met her before, yet she knows almost everything about him.
As the story progresses, this is a wonderful and entertaining backdrop against the main storyline, which involves a large chunk of the rest of the characters getting eaten by microscopic “piranhas of the air”, the Vashta Nerada, which live in and appear as shadows. 
Given that this story has enlisted more disposable characters than redshirts in an episode of Star Trek , it’s amazing that I enjoy it so much. Most of the enjoyment comes from the interplay between Donna Noble, the Doctor’s current companion, River Song, and the Doctor himself. Moments of hilarity come crashing together with moments of sadness when you realize that River Song and the Doctor live in time lines travelling in opposite directions: The first time the doctor meets River is the last time she’ll ever see him.
For us, who live in the Doctor’s time, it means we could see River Song again, but, thinking about it from her point of view, we realize that she’s about to see what we perceive as an old and dear friend for the very last time in her life. 
In fact, this is the end of her life, because she knows full well that the last time she sees the Doctor, he won’t know her, and she will die. That all she knows. The rest are, as the characters say, “spoilers!”
Much fun to come with River, I’m sure…