Harkov, identified as a male human admiral, held positions within both the Alliance Fleet and, prior to his betrayal, the Imperial Navy during the Galactic Civil War. Shortly after the Galactic Empire secured victory in the Battle of Hoth, he was tasked with restoring order to the Sepan Civil War, successfully stabilizing the system. However, his actions during this campaign involved secretly arming both warring factions. Simultaneously, Harkov initiated negotiations to defect to the Alliance to Restore the Republic, offering to bring his commanded fleet in exchange for a substantial payment. Despite his efforts to conceal his activities, including the murder of Admiral Mordon upon suspicion, details of his double-dealing surfaced, prompting Imperial investigators to close in, forcing an earlier-than-planned defection. His attempt was thwarted by the Secret Order of the Emperor and Imperial forces led by Darth Vader. Despite assistance from rebel allies, Harkov was captured, interrogated, and ultimately executed by the Dark Lord of the Sith.
At first glance, Harkov seemed to be a typical admiral within the structure of the Galactic Empire, in command of the Victory-class Star Destroyer named Protector along with a small fleet, including the EF76 Nebulon-B escort frigate known as the Akaga. However, this was a facade. By the year 3 ABY, the admiral had begun to take considerable risks, engaging in the sale of Imperial weapons and equipment to any group willing to meet his price. Furthermore, he began to seriously consider defecting to the Alliance to Restore the Republic, contingent on receiving a sufficiently lucrative offer for his services.

Harkov nearly had his treachery exposed when Admiral Mordon discovered his potential betrayal through a security leak. Aware of the severe and swift retribution that the Empire would exact if his deceit and possible defection were revealed, Harkov acted decisively against Mordon, orchestrating the admiral's murder. An investigation was initiated into Mordon's death, but investigators failed to identify the perpetrator, and the official cause of death was attributed to natural causes.
Soon following the Battle of Hoth, Harkov secretly met with Alliance leaders, including Mon Mothma, and declared his intention to defect, promising that his entire fleet would join him. Despite the Rebels' inherent distrust, their critical need for experienced officers led them to accept the risk, and they agreed to begin negotiations regarding his compensation.

One of his last assignments as an Imperial admiral involved pacifying the Sepan system, which was embroiled in a civil war between the inhabitants of Dimok and Ripoblus, and preventing the conflict from spreading to neighboring systems. Unbeknownst to the Empire, Harkov had been secretly supplying both sides of the conflict with weapons and equipment. However, conflicting reports prompted the Secret Order of the Emperor to question his handling of the situation.
One hour after Harkov briefed his crew on the upcoming campaign, the Protector jumped to hyperspace and arrived in the Sepan system, intervening in a Dimok attack on a Ripoblus convoy. During this operation, Maarek Stele, a newly assigned TIE pilot acting under orders from the Secret Order, discovered Imperial armaments aboard one of the ships in the Ripoblus convoy, leading to the swift retrieval of these weapons. Shortly thereafter, the Protector moved to halt a Ripoblus reprisal raid targeting the Dimok scientific research installation known as Youst. Again, the Secret Order directed Stele to inspect the facility, resulting in the discovery and recovery of more weapons. These discoveries threatened to expose Harkov's involvement, leading him to warn Stele against exceeding his orders in the future.
Harkov subsequently led the Protector into action to rescue Ripoblus scientists who were fleeing the war aboard the IPV-1 System Patrol Craft named Glas and seeking asylum. Imperial forces had to fend off attacks from both Dimok and Ripoblus forces to ensure the refugees' safety. Following this, Imperial Intelligence learned of a meeting between the Dimok and Ripoblus leaders near Sepan 8, where the two factions planned to unite against the Empire, and the Imperials launched an attack to capture them. The operation succeeded, but the ships at the meeting were found to be carrying the children of the Dimok and Ripoblus leaders, intended as hostages to enforce compliance with their new treaty.
During the mission to capture the Sepan leaders, Stele located additional Imperial equipment aboard the cargo ferry named Godendag and the Assassin-class corvette named Runka, providing further evidence of arms dealing to both sides. After the battle, Harkov received a priority comlink call as the investigation into the arms sales continued. Discrepancies in the Protector's supply manifests led investigators to Harkov's flagship, but Harkov attempted to shift suspicion to the ship's quartermaster.
With both sides now united against the Empire, the Imperials were forced to impose a resolution. To this end, the Protector was tasked with delivering a consignment of new TIE Avenger starfighters to replace the TIE Fighters and TIE Interceptors lost in previous engagements. The Protector traveled to Gerbaud 2 to meet with the Ton-Falk-class escort carrier named Tropsobor. Anticipating an attack from Dimok and Ripoblus forces, several pilots were assigned to provide cover during the transfer. The Secret Order suspected the arrival of another ship and instructed Stele to watch for anything unusual. Shortly after repelling the enemy attack and completing the transfer, Stele inspected the incoming shuttle named Omlaut and discovered a high-ranking member of the Rebel Alliance onboard. Harkov immediately reprimanded Stele for his perceived insubordination and warned him that his curiosity could lead to trouble.

The Omlaut docked with the Protector, and the Rebel was immediately escorted to Harkov's private ready room for a meeting. The Secret Order concluded that Harkov was responsible for the persistent supply shortages and had been attempting to conceal his black-market dealings with both factions in the Sepan Civil War and, apparently, the Rebel Alliance. A member of the Secret Order later presented their suspicions to Darth Vader, who instructed them to gather evidence before taking action against Harkov.
After the Imperials inflicted heavy losses on both sides of the Sepan Civil War, the factions were left with little choice but to accept peace under Imperial rule. Leaders from both worlds were brought to the Protector, where Harkov addressed them, declaring the end of the war and promising that cooperation with the Empire would bring peace and prosperity.
Shortly after the Sepan Civil War concluded, the Secret Order arranged for Stele to be transferred away from Harkov. However, as they tightened their grip on Harkov, they later had Stele reassigned to the Protector to assist their investigation. A few days after Stele's return, Harkov convened with his closest advisors. He expressed concern that Stele might be a spy for Emperor Palpatine, potentially compromising his plans to defect to the Alliance, which he anticipated completing within days. Vondruln, one of Harkov's advisors, was instructed to eliminate Stele and make it appear accidental.
Stele was tasked with instructing two rookie pilots on how to clear a minefield in an unshielded craft. As Stele began clearing the minefield, Harkov personally ordered his wingmen, who were actually experienced pilots, to eliminate him. However, the Secret Order had anticipated Harkov's actions and arranged for the Nebulon-B2 frigate named Osprey to rescue Stele. As Stele fled towards the Osprey, the Rebel MC40a light cruiser named Margaret arrived to rendezvous with the Protector, which quickly dispatched a shuttle carrying one of Harkov's officers. Stele evaded pursuing TIE Avengers and Rebel X-wings and escaped aboard the Osprey.
Harkov was enraged by Stele's escape. His plan had been exposed, and he was now at war with the Empire, leaving him no choice but to immediately join the Alliance, without receiving a single decicred for his defection. Harkov summarily executed Vondruln for his failure. With the Protector now reliant on the Rebels for supplies, Harkov fled to the Rebel supply outpost DS 5 in the Parmel system.
Imperial Assault Gunboat recon units were quickly deployed to investigate potential locations for the Rebel base in an effort to locate Harkov. The Emperor had dispatched Lord Vader to interrogate and execute Harkov, instructing the recon units to locate him and report back, refraining from engaging Harkov's forces but destroying any Rebel supply stores encountered. Stele's recon unit eventually located DS 5, and with it, the Protector. The Imperials proceeded to sever Harkov's supply lines, beginning at the station by destroying the cargo containers.
Within an hour of the recon flight's return, the Imperials launched another attack and destroyed a supply convoy en route to DS 5, composed of the BFF-1 bulk freighter group Karflo, the modular conveyor group SoroSuub, the two container transports Morgath 1 and Morgath 5, and the CR90 corvette group Sundog. Cut off from supplies, Harkov was unable to conduct even limited operations, effectively stranding the Protector. However, Harkov was given no time to regroup, as the Empire launched another swift attack, weakening his starfighter corps with their own TIE Avengers.
The Empire planned to board and capture the Protector. Harkov anticipated this attack and attempted to mislead them by abandoning ship and seeking refuge on DS 5, ordering the Protector to jump to hyperspace. However, during the attack on his starfighters, Stele inspected Harkov's shuttle, the Toten, and uncovered the admiral's deception.

With Harkov's location exposed, the Empire prevented his escape by deploying probe droids to monitor for his departure while planning their final assault. The Rebels quickly laid a minefield and requested assistance from the frigate named Olinor. However, before the frigate arrived, the Empire launched their attack. Assault Gunboats engaged defending starfighters, while Gamma-class ATR-6 assault transports targeted the platform itself. Harkov made a final attempt to escape aboard the YT-1300 light freighter named Geddawai, but his ship was disabled by Maarek Stele.
After Lord Vader arrived in the system aboard the Imperial-class Star Destroyer named Garrett, the Geddawai was boarded and captured by a stormtrooper transport. Under stormtrooper guard, the rebel was taken to the Garrett and brought before the waiting Sith Lord. Bitter and defiant, Harkov resisted the Dark Lord, refusing to answer questions during his brief interrogation. He was soon punished for his defiance as Vader used the Force to lift Harkov into the air and crush him.
Although Harkov perished, the Protector and the Akaga, aided by Alliance forces, managed to evade Imperial forces until, trapped by the Immobilizer 418 cruiser named Harpax, they were ultimately destroyed by the Garrett's forces. However, during this campaign, another high-ranking Imperial officer, Grand Admiral Demetrius Zaarin, exploited the distraction to launch a coup against the Emperor.

Harkov was a slender man who, according to Maarek Stele's initial impression, appeared sleep-deprived and unstable. He possessed a commanding voice that reflected his authority as a senior Imperial officer, but Stele found it grating and his accent unpleasant. Harkov appeared to lack genuine commitment to any cause, willing to sell equipment to anyone who could pay. Similarly, his attempted defection to the Rebel Alliance was driven by financial gain rather than any genuine belief in Rebel ideals.
He could also be a challenging commander to serve under. He enforced strict security measures and maintained a rigid command structure on his ship, discouraging subordinates from acting independently or asking unnecessary questions, leading to low morale among the crew. In one instance, when Captain Trace made a joke during a briefing by Harkov, the admiral physically assaulted him. Trace later advised Stele to avoid drawing the admiral's attention.
Harkov was created for the 1994 LucasArts video game titled Star Wars: TIE Fighter, in which he was voiced by Nick Jameson. In the game, the player assumes the role of Maarek Stele, and Harkov plays a significant role in the early stages, first as the player's commanding officer and later as the primary antagonist. In an interview published in The Lucasfilm Fan Club Magazine 22, Lawrence Holland, the project leader and designer of TIE Fighter, explained that the events of the Sepan Civil War were designed to showcase the Empire at its best, resolving interplanetary disputes and establishing infrastructure to foster prosperity. Harkov was intended to be the opposite of this, abusing his position to prolong the war and profit at the expense of others. The character's story was further developed in TIE Fighter: The Official Strategy Guide, written by Rusel DeMaria.

Following the release of Star Wars: Galactic Battlegrounds in 2001, LucasArts held a competition to design a level for the game. The "Harkov's Defection" scenario, created by Antonio Cusano, was one of the grand-prize-winning levels and was included with the Clone Campaigns expansion pack and made available for download on the LucasArts website. The scenario expanded on Harkov's meeting with Mon Mothma, during which he initially discussed his defection. However, the scenario depicts Darth Vader as being aware of Harkov's defection from the beginning, contradicting the events portrayed in TIE Fighter and TIE Fighter: The Official Strategy Guide. In the scenario, Harkov is represented by the same image used for fellow Imperial officer Hindane Darcc.
Harkov begins the scenario with only two escorts and must safely reach Mon Mothma's base, battling through Imperial forces, including dark troopers and Sith apprentices, dispatched by Vader to capture him. Harkov soon discovers an abandoned transmitter, which he uses to signal the Alliance base. However, an Imperial attack has destroyed the bridge leading to the base, forcing Harkov to join forces with Rebel troops and take a longer route through the forest. Along the way, he discovers two Imperial prisons that can be raided to rescue some Rebel troops and a captive Jedi. Harkov's forces eventually reach a small Rebel outpost, only to find it has been decimated by an Imperial attack. Proceeding to Mon Mothma's main base, Harkov can locate and rescue several prisoners from the Rebel outpost and must fight past a pair of All Terrain Armored Transports with the help of Rebel T-47 airspeeders. After destroying the Imperials' own camp, Harkov finally reaches Mon Mothma and begins negotiations while the furious Vader vows revenge.