Derek-142, also known by his alias of Control, was a SPARTAN-II supersoldier trained under the SIGMA detachment. An orphan before his recruitment into the program, Derek was quickly singled out for his high intelligence and brilliant strategic thinking during training and was to be fast-tracked to an officer's position within ONI before he 'washed out' during his augmentation procedures. In spite of this, he would eventually undergo successful rehabilitation and was assigned to the highly secretive Red Cell unit by 2528.
The Spartan would soon become the counter-terrorism unit's key to success as it staged mock attacks on numerous military installations and provided invaluable information for important facilities to defend themselves against Insurrectionist attack. Though Red Cell's importance would begin to dwindle as the Human-Covenant War raged across the Outer Colonies, Derek would serve diligently until 2532, when shortly after gaining control of an experimental and dangerous program known as Project OVERSIGHT the Red Cell unit's home base was destroyed as the colony world of Sansar was glassed. Leading the survivors of the attack offworld, Derek would not return to the UNSC and instead chose to fight the Covenant on his own terms, utilising OVERSIGHT to procure resources as Red Cell went rogue.
Derek would retain tight control of Red Cell for the entirety of the Human-Covenant War, though his tactics became more dubious as his subordinates attacked not only Covenant military targets, but UNSC facilities in the name of keeping their vessel running. His illicit actions would reach a high point in 2552 when Derek orchestrated the kidnapping of four Spartans, including a fellow Sigma member, during the Fall of Reach. Continuing Red Cell's covert actions even after the war's end, Derek would eventually become disillusioned with the Office of Naval Intelligence's leadership and formulated a plan to place himself in a position of power by making it seem as though he had saved the organisation from disaster after years of working in the shadows.
Ultimately, Derek's attempted coup in May of 2558 would end in failure. In spite of his control of the OVERSIGHT system, after the actions of several ONI agents, Sigma Team and treachery from within Red Cell itself led to his defeat. With everyone else in Red Cell dead, Derek was captured by his fellow Spartans and handed over to the authorities. ONI would sentence him to life imprisonment within the Midnight Facility, where he would languish for the rest of his days.
Derek Strepp was born in the town of Belisk, on the colony world of Sargasso. Shortly after his birth, his parents put him up for adoption, leaving him in state care for his early years. Due to the world's affluence compared to many other colonies, Derek and the other children in the orphanage enjoyed a fairly stable, happy environment and had few troubles. An innately curious child, Derek was noted for developing quicker than many of his peers, both physically and mentally. His carers noted his ability to read and write by the age of five, which attracted some attention from local schools looking for gifted children and promised a bright future for the young boy.
In 2517, Derek was among those who underwent the widespread Outer Colony vaccination program, and was visited shortly after by agents from the Office of Naval Intelligence. Pretending to be a couple looking to potentially adopt Derek, the pair asked him numerous questions about his life before leaving. While their abrupt departure surprised him, Derek was overjoyed at the prospect of adoption and eagerly awaited their return. That day would never come, however, as shortly after the interview he was sedated and kidnapped from the orphanage and replaced with a disposable flash clone. When he awoke, Derek was on a military transport ship en-route to humanity's homeworld, Earth.
Absolutely terrified, Derek did nothing to resist his captors as he was taken to a secret facility located in the United Republic of North America, where he met with nineteen other children of a similar age. There, they were formally inducted into the SPARTAN-II program as part of its offshoot: Project SIGMA. While most of the children understood little of their introductory speech, given by a man named Calvin Roe, Derek was quicker on the uptake than most and understood that he had been recruited into the military. After meeting their head trainer, Richard Mack, Derek - now Derek-142 - and the others were thrust into an utterly brutal training regime that pushed their minds and bodies to the absolute limit.
Unlike some of the others, it took Derek some time to properly adapt to the physical part of their military training. He would often lag behind and found himself unable to continue, often accepting help from his peers when he could. As their exercises changed into team games, Derek discovered a fondness for tactics and would often attempt to outsmart the other trainees and their drill instructors during team games. However, he lacked charisma and rarely found himself in a leader's role, finding cooperation difficult. With a preference for giving precise orders for others to follow than working alongside his peers, Derek found himself struggling in exercises that involved others.
While his field scores were never the best, Derek greatly outstripped everyone else in SIGMA when it came to their education, attaining consistently high marks in all subjects taught to the Spartan trainees. He became rather fond of Leon, the artificial intelligence overseeing their tutoring, and developed a keen interest in AI as a result of their conversations. However, Derek never developed any particularly close friendships with anyone else in SIGMA, and even harboured some private resentment towards a few of the other trainees. In particular, he found Marco-035's habit of questioning orders and Jack-085's ultra-competitiveness particularly infuriating, though he never spoke up about it. While he continued to excel mentally, Derek's lacklustre performance in combat had him stuck in the dead centre of SIGMA's leaderboard, which ranked the trainees according to test scores.
Towards the end of his training, Derek was privately informed by Mack that the Office of Naval Intelligence, impressed by his mental acumen, intended to make him an officer for a special counter-terrorism unit. While his trainer voiced his concerns and expressed an idea to keep Derek alongside his brethren, the young Spartan saw no problem with this, believing himself to be above the other trainees in many aspects. in 2525, Derek and the rest of SIGMA would undergo a series of procedures that would physically improve their bodies in every conceivable way; the final step in becoming a Spartan. Looking forward to what seemed like a promising future working for ONI, Derek attended a brief party alongside his fellows shortly before the procedures were to take place, and found himself genuinely enjoying the company of his fellows for the first time.
All of Derek's dreams would seemingly be for naught when, in the midst of his augmentations, his body began to reject some skeletal modifications. This would elicit a fatal response from Derek, who died and was immediately resuscitated twice on the operating table before his condition was stabilised and the procedures halted. When he eventually awoke, Derek was greeted by Richard Mack, who informed him that he had been the only one in SIGMA to 'wash out' while receiving his augmentations. Utterly distraught by this, Derek pleaded with his trainer for them to try the procedure again, even if it killed him. While alternatives were offered to Derek, whose body was damaged but recovering, he did not relent and eventually convinced Mack to allow him to try again. After making a promise to the old soldier that he would do his best to save lives, Derek was left alone to recuperate.
The recovery process was a difficult one for Derek, who resided in the mostly-empty SIGMA facility for months with very little contact with the outside world. Doctor Roe would visit him occasionally with updates on how his fellows were progressing, eventually informing him of Jack-085's sudden escape and the subsequent death of Ahmad-126. This shocked Derek, who in spite of his dislike of the other Spartans had never thought them capable of genuine desertion. While he asked Roe for permission to lead the hunt for Jack after his augmentations were successful, the scientist denied his request, stating that it was out of his hands. Four months later, Derek would undergo his augmentation procedures yet again only to meet the same near-fatal issues that forced doctors to abort the operation. While he was bedridden for weeks after, there had been some improvement compared to his first attempt, and Derek refused to give up on his goal of becoming a proper Spartan.
It would take nearly two years and three more attempts before Derek-142 fully received all of the mental and physical enhancements, with each failure leading to a much longer recovery time as he grew older and out of the prime augmentation age. In the downtime between each attempt he had been put to work by the Office of Naval Intelligence's Section One, analysing reports from Outer Colony worlds of rebel activity and helping to devise countermeasures against them. While young, Derek's impressive insight was valued by those he corresponded with, and by 2528 he was finally ready to leave Earth and begin work as a proper field agent. After being given the officer's rank of Lieutenant, Derek travelled to Reach, where he first met with Captain Cynthia Hale. As someone interested in the young Spartan's intellect and capabilities, she would introduce him to a secretive counter-terrorism division, known as Red Cell.
Over the course of a week, Derek would learn everything there was to know about Red Cell, whose role was to analyse and test the defences of important civilian and military facilities within the Inner Colonies in case of an actual Insurrectionist attack. While it began as a think tank, extra funding as rebel attacks increased allowed for field agents to exploit security weaknesses and improve their defences. Acting from Red Cell's base within an ONI-run bunker on Sansar, Derek and Captain Hale would plan over three dozen mock attacks within his first year with Red Cell, targeting buildings on Reach, Fargad, Miridem and even Mars as assignments were passed down from Naval Command. Derek would eventually begin leading these teams personally, not wanting his physical skills to go to waste. While some within the unit pointed out that the Spartan's enhanced physical prowess would allow for feats that no terrorist could feasibly accomplish as he planted fake bombs within Army bases and even stole classified materials from seemingly-impenetrable buildings, his undeniable success would give Red Cell more funding to expand their operations and led to genuine security improvements following their missions.