Jack
Subject Zero and Human Biotic
Jack, known to Cerberus as Subject Zero, was among the most powerful human biotics alive, forged by years of brutal experimentation she answered with a violent and bloody life. Recruited by Commander Shepard, she sought closure at the facility that had made her and later found purpose teaching young biotics.
Jack, also known as Subject Zero and by the name Jacqueline Nought, was a human biotic counted among the most powerful of her kind and a notorious criminal whose record ran to piracy, kidnapping, and murder. Made dangerous by years of experimentation she had answered with a lifetime of violence, she was held in cryogenic stasis until Commander Shepard bought her freedom and recruited her against the Collectors. Beneath her fury lay a survivor of one of the cruelest projects Cerberus ever ran, and her account is in large part the story of what she made of that.
Subject Zero#
Jack was born in 2161 and abducted by Cerberus operatives in 2165, taken for the biotic potential she had gained from accidental exposure to element zero in the womb. As a cover, her mother was told she had died. She became the central subject of a Cerberus project at the Teltin facility on Pragia, its aim to maximize human biotic potential at any cost. Designated Subject Zero, Jack received every enhancement that proved survivable, while many other children of lesser ability were treated as expendable and died in trials meant to ensure the treatments would work on her.
She was tortured both physically and psychologically to study how pain affected her abilities, kept apart from the other children, and forced to fight them in monitored bouts while drugged, conditioned to associate killing with euphoria. The other children, dying in experiments to advance her, came to despise her as the source of their suffering. Eventually, while being led to another experiment, the children rioted, and in the chaos Jack was freed. Her powers had grown beyond anything that could stop her, and she killed nearly everyone in the facility before stealing a shuttle and escaping Pragia.
A violent life#
After her escape, Jack lived a bloody life. To sever ties with her past she took the name Jack and reacted violently to her old designation. She ran with gangs, became a pirate, crashed a station into a hanar moon, and at one point joined a cult. The Teltin facility was shut down soon after her escape, and the Illusive Man later claimed he had been unaware of the brutality of its experiments and had closed it once he learned of it. Eventually Jack was captured and imprisoned aboard the Blue Suns prison ship Purgatory, where the warden, eager for the price she could fetch, locked her in cryogenic stasis.
Recruited by Shepard#
Shepard's team came to Purgatory to buy Jack's freedom. Her ordeals had left her unpredictable and deeply distrustful, unable to determine what the Commander wanted from her, yet beneath the hostility she remained tormented by her past and longed for closure. She joined the crew in exchange for the Cerberus files detailing her experimentation, and afterward asked Shepard to help her destroy the abandoned Teltin facility by planting a bomb in the cell that had been the source of all her misery.
On Pragia the two fought through mercenaries and encountered another former test subject, Aresh, who had hired them to restore the facility; Jack wanted to kill him, and Shepard could intervene. They planted the bomb in her cell and escaped before it detonated. If Miranda Lawson's loyalty had already been earned, a confrontation followed aboard the Normandy in which Jack demanded that Miranda admit Cerberus had wronged her, and Shepard could side with one, the other, or neither. Whether Jack survived the assault on the Collector Base depended, as with the rest of the crew, on the Commander's leadership.
The psychotic biotic#
If Jack survived the mission against the Collectors, she changed considerably. Approached by the Systems Alliance, she accepted a position teaching biotics for combat at Grissom Academy and agreed to temper her language to the standard expected of a teacher. Her unconventional methods served her students well, and they took to imitating her, even bestowing on her the affectionate title "the psychotic biotic." Having never had a family, Jack came to regard her students as one and swore retribution against anyone who harmed them.
Jack was present when Cerberus attempted to abduct gifted students from the academy, and she defended them, shielding her charges with biotic barriers until Shepard's team broke the assault. Together with Shepard and Kahlee Sanders she helped the students escape. Over the course of the war her students were sent either to the front lines or into support roles, and the path they took, together with whether Shepard reached the academy in time, determined Jack's fate. If the academy was not saved, she could appear later as an indoctrinated Cerberus husk, forcing the squad to put her down. If she lived, she fought on through the war, and in the accounts where the galaxy prevailed she was seen with her surviving students, looking toward whatever came next.
Frequently asked questions
- Who is Jack in Mass Effect?
- Jack, also known as Subject Zero and by the name Jacqueline Nought, was a human biotic counted among the most powerful of her kind and a notorious criminal whose record ran to piracy, kidnapping, and murder. Commander Shepard bought her freedom and recruited her against the Collectors.
- Why was Jack called Subject Zero?
- Jack was born in 2161 and abducted by Cerberus operatives in 2165 for the biotic potential she had gained from accidental exposure to element zero in the womb. She became the central subject of a Cerberus project at the Teltin facility on Pragia, designated Subject Zero, and received every enhancement that proved survivable.
- How did Jack escape the Teltin facility?
- While Jack was being led to another experiment, the other children rioted, and in the chaos she was freed. Her powers had grown beyond anything that could stop her, and she killed nearly everyone in the facility before stealing a shuttle and escaping Pragia.
- How did Commander Shepard recruit Jack?
- Shepard's team came to the Blue Suns prison ship Purgatory, where Jack had been locked in cryogenic stasis, to buy her freedom. She joined the crew in exchange for the Cerberus files detailing her experimentation, and later asked Shepard to help her destroy the abandoned Teltin facility.
- What did Jack do after the mission against the Collectors?
- If she survived, Jack accepted a position teaching biotics for combat at Grissom Academy, where her students affectionately called her the psychotic biotic. Having never had a family, she came to regard her students as one and defended them when Cerberus attempted to abduct gifted students from the academy.
Gallery



Images via Mass Effect Wiki
Sources
- WikiJack — Mass Effect Wiki entry
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