Lucius R. Jiron was a Commanding Officer of the stealth ship PRO-49776 and Office of Naval Intelligence operative during the Human-Covenant war.
In the year 2544, shortly after the Battle of Miridem, he recieved a narrow band point-to-point transmission from VADM Berlin M. Tursk regarding the capture of Doctor Catherine Halsey. Soon after, he was involved in the mission with a group of SPARTAN-II's which was led by Master Chief Petty Officer John 117 to retrieve Halsey from a Covenant fleet at some point before the Fall of Reach. He monitored the SPARTAN's mission from the bridge of the stealth ship. He then evacuated the remaining SPARTAN's along with Catherine Halsey.