Stewart was very intelligent, although not strictly in the "bookish sense". He was very disciplined, which he calls "knowing what you want", and his body was as disciplined as his mind; he was an avid practitioner of the martial arts. Ever since he was a child, Stewart had known what he wanted, and pursued it with a single-mindedness of purpose that stunned his allies and devastated his enemies. Stewart enjoyed the sensual aspects of life.
Stewart was captured by Kerrigan's zerg and transformed into a successful infested terran. His mind was damaged by a psi-screen, and even infestation was not enough to completely heal the damage. He quickly fell in love with her. As a zerg commander, he had a habit of riding a mutalisk.
Stewart met Rosemary Dahl, a fellow mercenary, in a drug den on the outlying world of Dead Man's Rock in 2496. He helped her overcome her addiction to stimulants and became her employer and lover. Seven years later he decided to leave the mercenary business and become a crime lord on that world, which meant he couldn't be around Dahl all the time (she was still conducting missions), but they still kept in contact.
Stewart "sold out" to the Dominion, creating a business relationship with the heir to the throne of the Dominion, Valerian Mengsk and possibly others, such as Arcturus Mengsk. The details of their arrangement are unknown, but Stewart made a great deal of money from it. He claimed that he legitimately found a source of extremely pure vespene gas when asked about his wealth. However, the arrangement had a downside as well; if Stewart didn't do what Valerian Mengsk asked, he would be killed. The Dominion was more than powerful enough to crush a crime lord like Stewart.
On the world of Nemaka, Rosemary Dahl and a team of mercenary marines guarded an archaeological expedition seeking the secrets of a strange artifact. The team was led by Jacob Ramsey, a maverick archaeologist in the employ of Valerian Mengsk, who was interested in the artifact. Ramsey discovered a secret in the artifact that overloaded his mind and literally rewired his brain. Valerian Mengsk (or someone else) intended to ship the barely-recovered Ramsey to a safe haven where ghosts would probe his mind and take from it everything of value, and then Ramsey would be killed. However, Ramsey's powers turned out to be stronger than expected; he and Dahl escaped the custody of the marines. Dahl, the more streetwise of the two, decided to head to Dead Man's Rock and hide out with Ethan Stewart. She did not know of his special arrangement.
Valerian Mengsk (or someone posing as him) ordered Stewart to send Jacob Ramsey and Rosemary Dahl to him. Valerian Mengsk promised Dahl would undergo "neural resocialization" to hide her memories of the interrogation. Stewart didn't want anything to happen to Dahl, and indeed didn't even believe Mengsk (despite nearly convincing himself that Dahl would survive), but had no choice in the matter.
Stewart was given a rough summary of Ramsey's abilities, and made sure to protect himself. He had been trained by Dr. Reginald Morris, a former employee of the Ghost Program, to use a psi-screen, a device to protect his mind from telepaths, which Valerian Mengsk had delivered to him as a gift. He hid the screen under a wig so expertly that his lover, Rosemary Dahl, never suspected a thing. He used the psi-screen to prevent Ramsey from reading his mind. Stewart even learned to control his external thoughts and "leak" them through the screen, which meant that Ramsey wouldn't just detect a void (and become suspicious), but would instead read whatever Stewart wanted him to read. He also seems to have learned much about the workings of the human mind. Stewart mentally trained in a set of caverns under his headquarters.
Stewart allowed Ramsey to read "cold-hearted" thoughts that Ramsey would expect a crime lord to logically have. Stewart would have used Ramsey as his own personal mind-reader, if he had the chance, so he allowed Ramsey to read that. He also let him feel his love (or something close to it) for Rosemary Dahl. Ramsey knew he couldn't stay with Stewart for long because the thoughts he was allowed to read frightened him.
Stewart couldn't have had a complete knowledge of Ramsey's abilities, however, which would lead to his downfall. Ramsey and his "protoss-in-his head", Zamara, experimented with the Khala, the psionic link that Khalai protoss share. Using the link, they were able to read Stewart's real thoughts, and discovered that he was selling them to Valerian Mengsk. Ramsey managed to convince Dahl to hack into Stewart's communication network, finding records of conversations between Stewart and Valerian Mengsk.
Dahl pretended not to know about Stewart's betrayal. She shut down cameras in strategic areas then pretended to seduce Stewart. Once she and Ramsey were close enough, she swiftly attacked him, shooting him in the arm and taking him hostage. Stewart tried to convince her to run away with him, but Ramsey used his new mind-reading abilities to scan his mind and inform Dahl of the deception. Dahl used Stewart to evade security, intending on escaping Dead Man's Rock with a ship she would steal from Stewart's spaceship hangar. Stewart's steward, Phillip Randall figured out what she was doing and ambushed Dahl and Ramsey.
During the ensuing battle between Ramsey and Randall, Zamara mentally took control of Ramsey's body and used a psionic energy attack as a last resort to kill Randall. Dahl shot her former lover without hesitation after boarding one of the transports and escaping Stewart's installation. The two fugitives then escaped as expected.
Stewart was very badly injured; he underwent six hours of surgery before the doctor noticed his psi-screen. She did not know how long he had been wearing it before, and decided to remove it to spare him any (more) possibly memory loss or brain damage. Shortly afterward, large numbers of zerg attacked the planet. A small number of zerg stormed his fortress, and a hydralisk spat a strange gooey substance on him, wrapping him in a web-like cocoon.
Ethan Stewart was brought before Kerrigan, and after some time emerged from his cocoon as an advanced infested terran. His new form was stronger and more resilient, with dark green skin, glowing green eyes, a lack of hair and an additional pair of scythe-tipped limbs extending from the middle of his torso much like a hydralisk's limbs. However, his voice remained unchanged, and his hands did not become deadly weapons. Parts of his brain were ruined due to the effects of the psi-screen, causing minor insanity. He also fell instantly in love with Kerrigan. Kerrigan believed this would make him easier to control and manipulate. She intended to use him as a general and consort, and quickly warned him about how she would kill him if he failed to be useful.
Kerrigan sent Stewart with a zerg force to Aiur to retrieve Jake Ramsey and Rosemary Dahl. He ambushed them as they left the underground chamber, telling them he wouldn't kill Dahl as long as Ramsey surrendered peacefully. Ramsey refused, and before Stewart's zerg could act they were ambushed by a force sent by Valerian Mengsk. The Dominion forces rescued Ramsey, Dahl and their Shel'na Kryhas protoss allies... but Dahl hijacked her dropship and flew it to the warp gate.
Stewart followed, riding a mutalisk. His attack was foiled again by the extremely powerful (and angry) Ulrezaj; he fell off his mutalisk and was saved from death by a pile of zerg corpses. He intended to personally prevent Ramsey from escaping, but Ramsey escaped through the gate.
Stewart tried interrogating the surviving Tal'darim how to use the gate, but they professed ignorance. He captured a wounded Alzadar, an influential Tal'darim, and tried torturing the information out of him, but Alzadar refused to give up any information and died. Kerrigan was displeased with him and repeatedly castigated him for failure, a habit she would continue.
Two days later, Stewart sent zerg forces into the caverns beneath Aiur to flush Ulrezaj out, as the zerg commanders believed Ulrezaj would know how to find the preserver. Ulrezaj had already regained much of his power and quickly slew many of the attackers but eventually fled in a xel'naga ship. Some zerg faked an attack on the ship while Stewart and other zerg got into a behemoth and followed. Ulrezaj headed to the moon of Ehlna.
Stewart's zerg surrounded the Alys'aril, the shrine Ramsey had been taken to. Executor Selendis, there with a small number of protoss warriors, convinced Stewart that Ramsey's operation was necessary. Stewart insisted on sending a single hydralisk spy into the shrine in order to observe. With little choice, the protoss agreed to his condition.
Ulrezaj reappeared on the battlefield, having recharged much of his energy. Stewart ordered numerous zerglings into the shrine while his heavier forces attacked the dark archon. The zerg were eventually stopped by a shield, which also slowed down Ulrezaj. A Terran Dominion fleet then appeared, joining the melee, and Ulrezaj suddenly disappeared. The Dominion defeated Stewart's already depleted forces and shot down the mutalisk he was riding. Stewart fell to the ground, suffering great injury. Rosemary Dahl approached, hoping to finish him off. Noticing the zerg weren't attacking her, she taunted him, saying his queen had abandoned him. Stewart, in love to the end, refused to believe Dahl. Before Dahl could shoot him, Selendis personally decapitated Stewart, in order to "protect" Dahl from her own desire for vengeance. Meanwhile, Kerrigan considered Stewart to be a failure, but the circumstances of his infestation a success. She could repeat it in order to create a new consort.
During his human life, Stewart employed a wide variety of individuals for various purposes. Known employees and servants include:
- Elyssa Harper (house maid)
- Janice Howard (chief surgeon)
- Sean Kirby (surgeon)
- Allison Lassiter (chief of security)
- Reginald Morris (psionics researcher)
- Stephen O'Toole (security guard)
- Phillip Randall (valet, assassin)
- Leeza (former employee)
- Samuels (surgeon)
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 Golden, Christie. StarCraft: The Dark Templar Saga: Firstborn. Pocket Star Books, May 2007. ISBN 0-7434-7125-3.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Golden, Christie. StarCraft: The Dark Templar Saga #2: Shadow Hunters. Pocket Star Books, November 27, 2007. ISBN 0-7434-7126-1.
- ↑ 3.0 3.1 Golden, Christie (June 30, 2009). StarCraft: The Dark Templar Saga #3: Twilight. Simon & Schuster (Pocket Star). ISBN 978-0-7434-7129-9.