Codename: SURGEON
From Halopedia, the Halo wiki
SURGEON was a code name used by a male ONI operative and leader of Operation: HYPODERMIC in 2552. "Surgeon" was contacted by Codename: COALMINER of a potential breach of security when Cortana broke into the ONI database and discovered that the Circumference was an ONI prowler. "Coalminer" then deleted the ship from the Reach database.[1]
NOTE: "Surgeon"'s true name and rank are unknown. It is plausible that he is Colonel James Ackerson but this is in no way confirmable. It is also possible that Surgeon is a medical doctor, similar to Dr. Halsey, in her command of the SPARTAN-II's. Surgeon is used once again in Halo: Ghosts of Onyx when a transmition about the S-III project is sent to him by Codename: COALMINER.
- ^ The Fall of Reach page 281