Charlotte Lux

Charlotte Abigail Lux, also known as CAL, was a human who later became a Node.

Biography
Charlotte was the youngest daughter of Strackman Lux's grandfather. Strackman Lux explained Charlotte was his aunt after the Doctor was shocked by discovering who CAL really was ("she's a child?!"). Felman Lux built his dying daughter The Library, its hard drive to contain and embody her living mind and a Doctor Moon to maintain The Library and her spiritual well-being. The library contained all of human history in it, which was perfect to keep Charlotte entertained. She loved books more than anything and her father gave her them all. Felman Lux also made sure that nobody outside of his family knew of the main command node's (Charlotte) true nature,; he wished for her to live in peace and not be treated like some kind of freak show.

When the Vashta Nerada began to hatch, CAL became aware of them. She tried to warn the people of the Library of the threat. The warning failed when the Vashta Nerada devoured the head librarian. She attempted to evacuate the people herself through the teleporters, but because the Library was now infested with Vashta Nerada,quarantining seemed hopeless. Instead of saving them, CAL "saved" the four thousand and more people to her system and the other nodes, putting them in a dream world to keep their minds occupied until rescue came. She then put herself into sleep mode because of the stress of having so many minds in her own. She forgot her true nature. She was watched over by the Doctor Moon that continued to function despite the disaster.

In her perpetual dream, she described to Dr. Moon a world she saw when she closed her eyes. It was the Library, where she encountered the Tenth Doctor and Donna. They came across a levitating wooden sphere, which, with a security camera, was her means of communicating with the world. In the dream world, she could contact the Doctor through her television screen, where they engaged in a brief conversation which was ended when the technology malfunctioned.



Shortly after this meeting with the Doctor, Dr. Moon talked with her. He shocked her by telling her that the people inside "her" Library were very real, that her "real life" was a lie and they needed her help. She interrupted the Doctor's teleporting of his companion to the TARDIS and unnecessarily "saved" Donna Noble, uploading her to CAL's hard drive and turning her into a Node, with her mind free to experience a dream life similar to that which Cal lived. She did the same with members of River Song's crew killed by the Vashta Nerada.

The Doctor and River Song realised what had happened to Donna had also happened to the four thousand twenty-two humans "saved" by CAL a century earlier. River sacrificed herself to allow these people to be "downloaded" and the Doctor fixed CAL's systems. In return, CAL provided a final home for the consciousnesses of River Song and her crew. Cal's sanity was restored and her computer avatar was adopted by River Song, along with Donna's children. (DW: Silence in the Library/ Forest of the Dead)