Catherine Halsey

Catherine Elizabeth Halsey, M.D., Ph.D. is a civilian consultant (#409871) (Civilian Identification Number 10141-026-SRB4695) to the United Nations Space Command Office of Naval Intelligence. She is a biological scientist, medical doctor, and an expert in computer systems.

Early Life
Dr. Halsey is an extremely intelligent and gifted woman, who, by the age of 15, was already working on her second doctoral thesis.

ONI Projects
Dr. Halsey made huge contributions to many ONI Section III projects including the creation and deployment of Artificial Intelligence constructs (such as Cortana). She also created the Spartan-II project and initiated the development of the MJOLNIR Armor Systems.

The SPARTAN-II Project
Dr. Halsey was the one who came up with the idea of the Spartan-II project. She built a set of rigorous genetic requirements that any potential candidate of the program had to meet. From these requirements, she identified 150 candidates, but ONI would only give her funding to train 75 of them. Along with Lieutenant, Junior Grade |Jacob Keyes, she met and interviewed each of the candidates and determined who the 75 would be. She then secretly brought the future SPARTAN-II's to Reach.

With the assistance of Chief Petty Officer Mendez and the AI Deja, she proceeded to train the Spartans. She supervised their augmentation procedures, combat training, and education, and studied the effects of the Spartan lifestyle on the children. She kept in close contact with them all throughout their lifetimes from her base under Reach. Annoyingly to the Spartans, she was always able to tell them apart from each other, even under half a ton of MJOLNIR battle armor. Dr. Halsey always used their first names, never their ranks or Spartan ID numbers.

Fall of Reach
After the Covenants invasion of Reach, Dr. Halsey volunteered to remain at ONI's CASTLE Base to destroy all the data that ONI had left behind. Fortunately, surviving SPARTAN-II soldiers found her and they were able to escape with a Forerunner Crystal ONI had been protecting.

Escape into the Unknown
Dr. Halsey later saw the importance of destroying this artifact, for it was too dangerous and uncontrollable to use. After escaping Reach, she stole a small spacecraft and, along with sedated Kelly-087, escaped into Slipspace. She entrusted the Forerunner Crystal to Corporal Locklear, telling him that if ONI obtained it, it could fall into the hands of the Covenant. Her whereabouts were unknown until the events of Ghosts of Onyx.

The Good Doctor Returns
In Ghosts of Onyx, Dr. Halsey and Kelly eventually make it to Onyx, while reuniting with SCPO Mendez and eventually her remaining SPARTAN-II's and the SPARTAN-III's. She helps decipher the mystery of the planet. At first, she tried to maintain secrecy about her intentions out of habit, until Kurt-051 confronted her about it. She admitted that she was not actually looking for weapons, but rather the secret Forerunner Shield World which she believed to be equivalent to a "bomb shelter." Her relative expertise with Forerunner technology was vital to the survival of the UNSC forces on Onyx. At the end of the Battle of Onyx, She, along with Mendez, Blue Team, and the Spartan-III survivors, found herself inside the Shield World, which she believed was actually a Micro Dyson Sphere.

Halsey's Guilt
Dr. Halsey carried extraordinary guilt because of the SPARTAN-II project, and she felt that she had exploited the children and destroyed their lives. Though she continued to support them and gain monumental prestige for her efforts, she also felt responsible for each one who died. She never could quite justify their exploitation as a "necessary sacrifice". This likely accounts for her actions in abducting Spartan-087.

Skills and accomplishments
Dr. Halsey has made numerous accomplishments over the years. Aside from being the Mastermind behind both the Spartan-II and MJOLNIR projects, she also supervised the creation of the third-generation Smart-AI template. She demonstrates extensive skills in hacking and decryption and is a mathematical genius.

Her experience and time with the Spartan-IIs give her the insight to be able to identify each Spartan even when they are wearing their MJOLNIR armor. She also attempts (and regularly succeeds) at portraying herself as omnipotent, particularly amongst the Spartans.

Appearances

 * Halo: The Fall of Reach
 * Halo: The Flood (mentioned)
 * Halo: First Strike
 * Halo: Ghosts of Onyx