Series 4 (2008)
Episode title: Forest of the DeadFeaturing: Tenth Doctor
Companions: Donna Noble, River Song
First shown: 7th June 2008
Related articles: Vashta Nerada
Guide: This is the concluding part of the two part story, which started with Silence in the Library (series 4, episode 8).
Proper Dave is hunting The Doctor and co. and a seemingly dead Donna is speaking from a node, and Vashta Nerada are coming round the corner towards the fighters. It appears that they are trapped, until River Song produces a square gun, last seen with Captain Jack Harkness in The Doctor Dances (series 1, episode 10), to clear a section of wall for them all to escape through.
But now, Other Dave also has two shadows, but no one realises it yet. The Doctor tells everyone to get space suits on and max them up, which can only be done with his sonic screwdriver. He tells River Song this, but she says no need to pass sonic screwdrivers around, because she has her own. When The Doctor asks where she got hers, she replies that he gave it to her, in his future.
The Doctor is getting angry now with River, because he would never give his sonic screwdriver away. Never ever never. But she needs him to trust her, so she leans into him and whisperes in his ear something which the audience isn't able to hear. After this, the Doctor trusts her completely, as he tries to find Donna.
Donna meanwhile is living a normal life somewhere that looks like Earth, gets married and has kids. Oblivious to anything the Doctor is doing. She has a doctor of her own, called Doctor Moon, who helps her forget the 'imaginery' memories of the Doctor.
The Doctor finds out that the Moon which orbits round the library planet, is called Doctor Moon, because it's an anti-virus programme, checking and cleaning the library of viruses. It looks over the hard drive, which is called CAL.
After breaking into the planets main-frame, the Doctor goes down into the core of the planet with everyone, except Other Dave who had been killed while Donna was getting married. But another of the crew has two shadows.
When he gets down to the core, the Doctor finds out that CAL is actually, Cal. A little girl who had a terminal illness and her last request was to live in a big library, so her family created the library planet, and placed her in charge as a node.
While everyone but the Doctor and the one with two shadows goes back upstairs to check on the computers, the Doctor knows that a third person is dead, standing behind him. Two shadows into one, she has been eaten by the Vashta Nerada. But the Doctor is not fazed, and continues his work, which she tries to stop.
She explains that the Vashta Nerada are home. This is their forest. The Doctor realises that they primarily live in wood, and wood was cut down and made into paper for books, and the Vashta Nerada came with them. But the Doctor retorts saying that they are in the biggest library in existance, so look him up. The Vashta Nerada decide to give him 24 hours.
The Doctor manages to work out how to get everyone out of the main-frame, including Donna, but he isn't allowed to do it. Just before he does it, he get's knocked out. When he comes to, he finds River Song about to do what he was going to do. He pleads with her to let him do it, but he's handcuffed and unable to stop her. River explains that they will meet again, but in his future, and that this was the last time for her. She explains that the worst bit was, when the two of them meet again, the Doctor knows how and when she dies. He then says that she told him his name (when she whispered to him). He didn't know why he would do that.
River does the deed to save everyone, but in turn dies. The Doctor is freed and ensures everyone leaves the planet for good. But he keeps pondering why he told her his name, and gave her his sonic screwdriver. But then he realises, and opens the screwdriver to find a little memory chip in, which preserved the memory of River Song enough that he could put her into the main-frame to live on in an imaginery world. He said that his future self was brilliant, because he knew how she died, so he know how to fix it.
The episode ends with Donna and the Doctor leaving, and River reunited in the imaginery world with her friends.
This is the second of a two part story. Read the first part here.