Doctor Carole Friedkin is an anti-Crey informant encountered in multiple missions from Gordon Stacy and the second mission of the Manticore Task Force. 'The Doctor' as she is often referred to, has no physical presence, instead passing information to characters through computers.
Dr. Carole Friedkin was an elderly Crey scientist who created a memory downloading process. She was murdered by Crey, and her body was found in the sewers five months after her disappearance. Crey has also filed a patent for an eerily similar 'Memory Transference Device'.
Her surname, "Friedkin", is sometimes spelled as "Friedken" in various missions.