Castellan, in the context of the BBC television series Doctor Who, is a title adopted by one or more high-ranking Time Lords, such as Castellan Spandrell, Castellan Kelner and the , who is/are member/s of the High Council of Gallifrey and is/are in charge of the security of the Citadel. The Chancellory Guard reports to a/the Castellan. It is unclear whether the times in office of the Castellans depicted in the series overlap or not.