Series 4 (2008)
Episode title: Silence in the LibraryFeaturing: Tenth Doctor
Companions: Donna Noble, River Song
First shown: 31st May 2008
Related articles: Vashta Nerada
Guide: The Doctor takes Donna to the biggest library in the universe. It's not just any old library, it's a library planet. Every inch of the planet is part of one large library, with the core being the hard-drive. When Donna asks why they've come, the Doctor reveals his psycic paper has a message, attached with it is also a little kiss (x).
As the Doctor and Donna burst into a small ante-room of the library near the exit, they meet more people. Professor River Song and co. have come on an expedition of the planet. The Doctor finds out that the planet was closed off over 100 years ago when a virus spread, killing humans. They reckoned it would now be safe to return for an expedition.
The Doctor tries to explain that it isn't safe yet, and that they all need to turn around and depart quickly, but they arn't having any of it. So instead, they all set to work trying to find out what happened in the past. The Doctor and River Song start to get to know each other, only to discover that she's met the Doctor before, in her past, but in his future. She also carries a little diary of his events, from his future, which he's not allowed to see.
After a little bit of working out, the Doctor realises the enemy that they're facing. The Vashta Nerada. Flesh eaters, who look like shadows, and caused so many races to have a fear of the dark. On Earth, they primarily feed on road kill, but in the library, they fed on the humans.
The Doctor announces that they all need to put their space suits on for protection, which Donna points out, they don't have. So the Doctor takes Donna into the little shop by the exit, and teleports her into the TARDIS, but she doesn't make it.
Proper Dave suddenly has two shadows. One is his own. The other, the Vashta Nerada. Unfortuanately the Doctor cannot save him, so him and the others flee, but Proper Dave follows, as a skeleton who's been eaten. The Doctor looks to a node for help, but when the node turns round it's the face of Donna. The episode ends with Proper Dave hunting them, and the face of a seemingly dead Donna speaking over the top.
This is the first of a two part story. Read the second part here.