SCP Theme: Isd 'Internal Security Department' 

ISD is a concealed "foundation within the Foundation", a secret police force responsible for filtering traitors as well as operational and information security risks among the Foundation's ranks. The department is strictly hierarchical, adhering to stringently defined multi-stage investigative protocol. Potential ISD agents must have a perfect service record and a length of Foundation service of more than a year. Usually, every ISD agent keeps his "official" position in order to provide his command a first-hand account of everything happening in a given department. The very existence of ISD is usually presented as a myth. The "official" responsibility of ISD is investigation and interrogation of captured GOI agents, although that part of ISD officially belongs to Security Department for the purpose of secrecy.