Description: The Doctor and Donna join a group of archaeologists at a 51st century library. What caused the library to become abandoned? What are the Nodes? And what links the library to one little girl? All they have is one warning - count the shadows. //// The Doctor and Donna land in the 51st century to visit the greatest library in the universe. The Doctor is somewhat taken aback however to find there is no one there. To the best he can determine, the library has been closed for 100 years so the arrival of a team of archaeologists comes as something of a surprise. The private expedition has been paid for by a wealthy amateur but the expert leader of the group is Dr. River Song. Although the Doctor doesn't know her, it soon becomes apparent that she knows him quite well having met him in another time. All of them however come into danger when they make contact with a young girl who communicates with them through her television. The encounter has consequences for Donna in particular who seems to have been absorbed into the library.