Serin Osman

Rear Admiral Serin Osman, born Serin Çelik, formerly SPARTAN-019, also known as Oz, (service number 39489-72738-SO ) is the Commander-in-Chief of the Office of Naval Intelligence, inheriting the role from Admiral Margaret Parangosky after the end of the Human-Covenant War.

Early life
Born in 2511 on the colony of Cascade, Serin Çelik was the daughter of Pinar Çelik, a prostitute and drug addict. Her childhood was tough, having to dig through garbage cans for food. Without the support of her mother only her teacher, Alkmini Leandro, fed her and raised her. In 2517, she was abducted as a SPARTAN-II candidate. She was given the designation Serin-019, and trained under Chief Mendez along with the rest of the SPARTAN-II candidates. Because of her living conditions, she was one of the few candidates that was not replaced with a flash clone. During the program, she was known to eat leftover foods from the other candidates, for which John-117 teased her.

SPARTAN-II Program and ONI career
"BB sometimes wondered what kind of operational Spartan she would have made, just the averagely terrifying kind or a full-blown angel of death."

- Black-Box

Osman did not successfully complete the augmentation process, only receiving the genetic and biochemical enhancements before her body started to reject the rest. While she failed the augmentation process, she still possesses a few of the enhancements, although nothing skeletal. At 14 years old, the Office of Naval Intelligence took custody of her, educated her further, and put her into the ONI commanders' program. They also repaired the damage done by the failed augmentation process, but the other Spartans thought her dead; unlike some of the other washouts later assigned to ONI, she was withdrawn from the program before the funeral ceremony for the Spartans killed in the augmentations. As a result, she remained unaware if the successful Spartans were even told of the fate of the failures.

Considered as a protégé to Admiral Margaret Parangosky, the Director of Naval Intelligence, the Admiral groomed the former Spartan for a potential future as her successor. Osman considered herself the only person who the Admiral would always forgive even if she failed. In order to hide her status as a former Spartan, she adopted the surname "Osman". Though people often assumed she was of Turkish descent based on her name and appearance, she did not actually know whether this was the case; though the information on her pre-Spartan identity was readily available to her, she did not look at her personal file for decades, until spontaneously deciding to do so in April 2553.

Kilo-Five
By 2553 Osman held the rank of Captain. She was hand picked by Parangosky to lead up a black operations team known as Kilo-Five, which was composed of smart AI Black Box; a civilian professor and Sangheili expert Evan Phillips; ODSTs Staff Sergeant "Mal" Geffen, Sergeant Lian Devereaux, Corporal "Vaz" Beloi; and SPARTAN-II Naomi-010 to ensure Sangheili insurgency. Using Phillips, Osman got a meeting in January with Avu Med 'Telcam, a member of the Servants of the Abiding Truth on New Llanelli. She agreed to give him weapons to aid in his upcoming insurrection, but it was part of a ploy to destabilize the Sangheili. Later she met with Parangosky to confirm Kilo-Five's members, as well as being given the AI Black-Box and a secondary mission to find Dr. Catherine Halsey who had disappeared with Blue Team after the Battle of Onyx. Upon arriving aboard the Osman transitioned the ship into slipspace, and told Naomi-010 who she was. Naomi-010 revealed to Osman that they thought she had died. Osman then proceeded to tell the others about her past in the SPARTAN-II program, revealing that it started when she was six. This shocked the other members on the ship and angered Naomi-010, creating the very tension Osman had hoped to alleviate. Reaching New Llanelli, Osman was surprised to see 'Telcam had kept his word, and gave him tagged Sangheili weapons.

However, she was approached by Tom Muir, a colonist who had managed to survive on New Llanelli even with the colony's glassing. Brought aboard the ship, Osman was angrily questioned by Muir about why she was meeting with the Sangheili. Osman made up a story that they were exchanging fallen bodies that Muir bought into, saving Osman from needing to kill him. After a quick mission extracting Mike Spenser from Reynes, Osman went to aid the that was damaged outside Venezia. However, the ship was destroyed by Venezia.

She went on several missions aiding the Servants of the Abiding Truth and continuing the insurrection against Arbiter Thel 'Vadam, and even taking Dr. Catherine Halsey into custody for "committing acts likely to aid the enemy" and meeting with Fred-104, Kelly-087 and Linda-058 and the Spartan-IIIs Tom-B292, Lucy-B091, Ash-G099, Mark, Olivia and Chief Mendez in Shield World 006.

After 'Telcam began an armed insurgency against 'Vadam, Parangosky ordered Osman to intervene during the Servants of the Abiding Truth's attack on Thel 'Vadam's keep. While the Lord Hood and the UNSC Infinity openly aided 'Vadam and defeated the attackers, Osman secretly destroyed several of 'Vadam's ships, allowing the Abiding Truth's forces to escape. Her team also rescued Evan Phillips, who had been stranded on Sanghelios previously. She also rescued 'Telcam (much to his anger) from 'Vadam's forces.

Venezia and Pious Inquisitor
After the operation on Sanghelios, Osman and her team were assigned to track down Naomi's father and known Venezian insurrectionist Staffan Sentzke, who was seen in the company of the Kig-Yar Skirmisher Sav Fel. Fel was known to have stolen the battlecruiser Pious Inquisitor, which Kilo-Five was tasked with tracking down. In April, during the mission, Osman was promoted to rear admiral and a small party was held aboard the Port Stanley in her honor by Kilo-Five (except Vaz and Naomi, who were on Venezia).

Eventually, Kilo-Five's mission of finding Pious Inquisitor was concluded with the ship's destruction and the presumed death of Staffan Sentzke, who Osman had previously allowed to reunite with his long-lost daughter Naomi. After the mission, Osman reported back to Parangosky and they discussed Osman's inheritance of the CINCONI's post and their future course of action with Dr. Halsey. Following this, Osman decided to read her own file, discovering that her origins were very unlike the idealized image of a happy family life she had previously imagined. She decided to visit Cascade and her former teacher Alkmini Leandro while the rest of the team were given a brief shore leave.

Requiem campaign
By 2558, Osman has risen to the rank of Admiral and had taken Parangosky's place as head of the Office of Naval Intelligence. During the later stages of the Second Battle of Requiem, she was contacted by Captain Thomas Lasky, informing her about Doctor Halsey's abduction by the Promethean Knights. She had been recommended to either keep Halsey in confinement or have her executed, but instead chose neither. Questioning the doctor's loyalties, Osman followed Parangosky's advice and ordered Lasky to execute Doctor Halsey after years of reluctance.

Osman later served on the UNSC Security Council committee that debriefed Lasky and Palmer. She berated Lasky over Halsey's escape and the complete destruction of Requiem. Osman then questioned Palmer, who defended Lasky's actions to spare him of any ramifications from Osman.

Personality and traits
Due to Admiral Parangosky's long-time influence on her, Osman is virtually an extension of the former CINCONI's will; by indoctrinating Osman and arranging her to be the new head of ONI, Parangosky ensured that her legacy and policies would continue unchanged. Before her ascension to Parangosky's place, Osman still questioned the morality of some of the actions she and Kilo-Five routinely committed, such as actively working against the Arbiter's forces, although she never failed to follow Parangosky's orders. Years later, such concerns appear to have evaporated; for example, Osman coldly ordered the assassination of Dr. Halsey, though her lack of hesitation may also have to do with her antipathy toward the doctor, likewise passed on from Parangosky. As CINCONI, Osman has also inherited her predecessor's intimidating reputation; Captain Lasky, for example, was visibly nervous when contacting her about Halsey.

Osman is known to experience unusually strong symptoms involving vertigo and nausea during slipspace transitions. While she was away on a mission, Parangosky had crystallized ginger regularly shipped to her as a remedy.

Trivia

 * As a rear admiral, Osman is the highest-ranking Spartan of any generation.
 * In the audiobooks for the Kilo-Five Trilogy, the narrator voices Osman with a Australian accent, reflecting her background at Bravo-6 in Sydney. She speaks with an American accent in Spartan Ops.
 * Serin is unique among Spartan-IIs in that a flash clone was not used to replace her, as her retrieval team deemed that it wasn't appropriate. In her case, no one would be surprised if she went missing and substituting a clone would complicate things.

List of appearances

 * Halo: Glasslands
 * Halo: The Thursday War
 * ''Halo 4
 * Spartan Ops
 * Halo: Escalation
 * Halo: Mortal Dictata