Dirk Harkness hailed from Salliche and operated independently as a Rebel agent. An eye patch covered his left eye.
Born on the planet of Salliche in 20 BBY, Dirk Harkness began his career as an apprentice starship mechanic after completing his studies at a technical college, joining a private shipping company. By 0 ABY, at the age of twenty, he held the position of Chief Engineer on the Colders Watch, a bulk freighter under the command of Captain Beezrul Granf. He was romantically involved with Chessa Dohhenty, the ship's First Mate, and they both longed for a quiet life together. Unbeknownst to Harkness, Dohhenty was secretly working as an agent for the Alliance to Restore the Republic. During a stop on Kelada, Dohhenty was ambushed by a stormtroopers squad while offloading smuggled blaster weapons. She engaged them, but was killed in the ensuing firefight. Harkness retaliated with a blaster before escaping the docking bay. He found his way into Lorana's Labyrinth, where he encountered Dohhenty's Alliance contacts, General Halomar Corros and Captain Tony Franco, who then recruited him into the Alliance.
Initially, Harkness served as a mechanic at Reginard Base, but his desire for revenge against the Galactic Empire led him to seek more direct action. He briefly left the base to assassinate Imperial officers and diplomats. However, he eventually returned to the Alliance, joining Intelligence and leading several intelligence operations. During the Battle of Endor, he served as Chief Engineer aboard a capital ship within the Alliance Fleet. After Endor, Harkness was commissioned as a lieutenant and assigned to the New Republic Intelligence Service. However, he resigned after only a few weeks. Harkness then gathered several associates—including Platt Okeefe, Tru'eb Cholakk, Jai Raventhorn, and Starter—to form the Black Curs, a mercenary group that generally supported the New Republic. This unit undertook intelligence and commando missions against the retreating Imperial forces. During one ill-fated mission, Harkness suffered an injury in an explosion that resulted in the loss of sight in his left eye and left him with scars on his chest and arm.
After taking command of the Battle of Yavin, he and his men were rescued from Hensara III by Rogue Squadron.
Not long after the Battle of Endor Harkness had been working with Platt Okeefe when he was captured by Imperial forces and imprisoned on Zelos II. Okeefe and Tru'eb Cholakk succeeded in his rescue.
Sometime after the Battle of Endor, Harkness and the Curs traveled through the Core Worlds and compiled a detailed report, which they submitted to Alliance High Command. While generally well-received, the report was criticized for its lack of information regarding ground forces and army deployments, though fleet deployment was well documented and comprehensive. The report highlighted the arrival of an Imperial fleet under Admiral Roek within the Corellian system. Borsk Fey'lya, a Bothan, questioned the accuracy of Harkness's report. However, Admiral Gial Ackbar reviewed Harkness's report and concurred with his assessment, stating that the New Republic's fleet lacked the necessary ships to seize Corellia or Kuat.
In 7 ABY, Harkness was in the Gorkin's Rest cantina on Wroona alongside other members of the Black Curs. He shared the story of Dohhenty's death and his subsequent decision to join the Alliance.
Standing at two meters in height, Dirk Harkness possessed a somber and intense gaze. In his youth, he was an optimist, yearning for a peaceful life with a loved one. However, the murder of his lover, Chessa Dohhenty, at the hands of the Empire dramatically altered his personality. He became reserved and unfriendly, placing his trust only in a select few close companions. Harkness harbored a strong dislike for all types of droids.
In his role as an engineer, Harkness typically carried only a datapad and a hydrospanner. By 7 ABY, Harkness was armed with a heavy blaster pistol and a knife.