Sarah Gavin

Sarah Gavin was an intelligence agent at CTU Los Angeles.

Day 4
At the start of Day 4, Sarah was an analyst at CTU, working closely with Chloe O'Brian, Edgar Stiles, and Marianne Taylor. It is believed she often fought with Chloe, because Chloe told her something and Sarah called her a bitch. She also spoke irrationally to Samantha Caines a while later. CTU Director Erin Driscoll told her to spy on Chloe, because she believed Chloe was acting with Jack Bauer. Later in the day, when Chloe was escorted out due to working with Jack and stealing satellite, Chloe told Sarah that she was insulted more than mad. She said to use a Newman filter when pipelining someone's system so that they don't see red lights flashing everywhere. Later, Marianne, a mole at CTU working for the company McLennan-Forster, believed her cover to be threatened, she planted evidence implicating Sarah as the mole, and Sarah was promptly taken into custody.

When Sarah denied any knowledge of this, Erin authorized the use of torture to get her to cooperate. During the interrogation, she was subjected to electric shock. It is assumed that she was also subjected to a chemical. The chemical is possibly hyoscine-pentothol. Edgar eventually discovered evidence revealing Marianne as the true mole and Sarah was released.

Sarah would later demand a two-level pay grade promotion from Driscoll as compensation for her ordeal. Driscoll appeared receptive to this demand though she stepped down as director of CTU later that day for personal reasons. When Sarah attempted to make the same demand from Driscoll's replacement, Michelle Dessler, Michelle relieved her of duty, unwilling to deal with Sarah's personal disputes in the midst of a national crisis. Chloe (who had been relieved of duty by Driscoll for insubordination earlier that day) was reinstated to replace her.