Catherine Elizabeth Halsey, MD, PhD (SN: CC-409871),[11] was a praised scientist and former employee turned prisoner of the Office of Naval Intelligence, best known as the creator of the SPARTAN-II Program and Mjolnir Powered Assault Armor.
Despite being a civilian, she held considerable authority within ONI and commanded considerable respect from many military figures.[12] As she grew older, Halsey took various extreme measures to protect her remaining Spartans, even going against the military 