Miranda Keyes was the Commander of the UNSC ships In Amber Clad and Forward Onto Dawn. She was the daughter of Captain Jacob Keyes, who died in Halo: Combat Evolved from the Flood and Dr. Catherine Halsey. Commander Keyes, as she is often referred to, has a youthful physical appearance and short cropped black hair.
Miranda Keyes plays a critical role throughout the entire Halo series. She appears in many of the cutscenes in both Halo 2 and Halo 3, and her voice-overs help carry the story as well as giving the player instructions and information throughout the game. Along with Sgt. Johnson and Cortana, Commander Keyes is the primary source of intel and mission information for the Master Chief.
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Miranda Keyes died while trying to save Sgt. Johnson, who was captured by the Prophet of Truth. The Prophet of Truth was attempting to force Johnson to activate the Halos from the control room in the Ark (since only humans and Forerunners are able to). When Keyes arrived by crashing her Pelican through the wall, she attempted to take out all the Brutes and the Prophet, but then realized she was heavily outnumbered. Upon this realisation she trained her pistol upon Johnson, realising what she had to do to stop the Prophet of Truth from activating the Halo rings. Johnson urged her to kill him and herself, but she hesitated even as she aimed her gun at him, and then she was then shot several times from behind by a Brute Spiker manned by a Brute Chieftan, leaving her dead and Sgt. Johnson alive.