Office of Secret Intelligence

The Office of Secret Intelligence is an intelligence agency answerable only to the Emperor, tasked, among other tasks befitting a secret agency, with the capture of C.C. Its members appear not to have been informed of C.C.'s immortality, and only a few selected agents have been disclosed to the true power of Geass.

The entrance to the OSI is located behind a bookshelf. The bookshelf is a disguised door to an elevator that goes underground, where headquarters of the OSI is located.