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In October 2552, the Office of Naval Intelligence was conducting experiments on the Flood on the prison ship Mona Lisa in the Soell system near Installation 04's debris field. However, the parasite broke loose and infected most of the ship's crew and inmates.
Despite being gravely injured, with slashes across his body, a shattered shoulder and one ear missing, "John Doe" managed to survive the outbreak and board an escape pod, which was detected floating in space by the crew of the UNSC Red Horse. Immediately following the docking of the Red Horse with "John Doe's" escape pod, Sergeant Zhao Heng Lopez and her team opened the escape pod to find the man lying in a large pool of his own blood. Lopez tried to question him, but he was delirious and the only information he was able to provide was that he came from a ship called the Mona Lisa.
Aware that he was dying, "Doe" expressed relief over the fact he was not infected, and thus would not "come back." He succumbed to his wounds shortly afterwards, leaving the crew of the Red Horse puzzled. An autopsy was performed soon after by a medical technician known as Tsardikos, who, along with everyone who had come into contact with "John Doe", would then be sent on a reconnaissance mission to the Mona Lisa.
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