Forest of the Dead

"Forest of the Dead" is the ninth episode of the fourth series of the British science fiction television series Doctor Who. It was first broadcast by BBC One on 7 June 2008. It is the second of a two-part story; the first part, "Silence in the Library", aired on 31 May. In the episode, the time-travelling temp Donna Noble (Catherine Tate) is trapped inside a virtual reality in a planet-sized library's hard drive in the 51st century and has false memories implanted of a married life. At the same time, another time traveller, the Tenth Doctor (David Tennant), seeks to rescue Donna, and thousands of other humans saved inside the library hard drive while being pursued by the microscopic swarm called Vashta Nerada. The episode also features the death of River Song (Alex Kingston), an archaeologist who has a close relationship with the Doctor, but because of the non-linearity of this partnership, the Doctor in the episode has only just met River. Plot The Tenth Doctor, River, Strackman Lux, and the remainder of their team flee the microscopic Vashta Nerada on a planet-sized Library. Other team members are consumed by the Vashta Nerada, their space suits animated by the swarms. During a respite, Lux explains that the Library was constructed by his grandfather for Lux's aunt, Charlotte, who was diagnosed with an incurable disease at a young age. Lux's grandfather had a giant computer constructed at the core of the Library to allow Charlotte's mind to live on among the collected works of humankind. The Doctor realises Charlotte's mind is struggling to cope after "saving" the thousands of patrons by transferring their physical forms to the computer core 100 years ago when the Vashta Nerada attacked. Within the simulation of a contemporary Earth village, Donna is tended to by Dr Moon (an avatar of the virus checker program) and introduced to Lee, whom she marries. Aware that time is skipping, Donna is alerted by Miss Evangelista, one of River's team members killed by the Vashta Nerada, that she is in a simulation.