George "Digger" Harkness Secretly the illegitimate son of an American soldier and an Australian woman, Harkness was raised in an Australian town called Korumburra in poverty, during which time he developed great skill in making
boomerangs, and in using them as weapons. As a young adult, he was hired as a performer and boomerang promoter by a toy company which was, unbeknownst to him, owned by his biological father. It was at this time that he developed the Captain Boomerang persona that he would continue to use in his later criminal career. Audiences ridiculed him, and a resentful Harkness turned to using his boomerangs for crime. When he began committing crimes, he threw suspicion off himself by briefly pretending another man was impersonating him, showing his 'parents', (really other crooks) to the Flash after the Flash caught him next to a crime scene. He nearly succeeded in killing the Flash after knocking him out with a boomerang, then tying him to a giant boomerang that he fired, which then got sent into space and then fell into the ocean. However, the Flash escapes from his friction-proof bonds by quickly vibrating his molecules. He also increased the boomerang's velocity so much he was able to use it to defeat and jail Harkness and the two crooks. Boomerang becomes a recurring enemy of the
Flash and joins the
Rogues, a group of villains dedicated to opposing Flash. Later on, Harkness joins the
Suicide Squad in exchange for a pardon. In the
Blackest Night crossover, his remains are reanimated as a member of the
Black Lantern Corps, and he joins the reanimated Jack and Janet Drake, John and Mary Grayson,
Tony Zucco, and the original Batman's deceased rogues gallery members in an attempt to kill
Batman and
Red Robin. Digger manages to escape and join in the mass battle against the heroes where he is brought back to life and rejuvenated. He appears confused as to what is going on before being knocked out by the Flash. Following his resurrection, Captain Boomerang is at one point contacted by the
Life Entity, who instructs him to throw a boomerang at
Dawn Granger. After seeing the vision, his powers go out of control, causing him to attack everyone, including his fellow Rogues. Afterwards, Captain Boomerang sneaks into Iron Heights, where Professor Zoom is locked up. Boomerang releases him, in hopes that Zoom might help him better understand his version of the Entity's message. However, Zoom refused to answer and escaped as Digger was confronted by the Rogues. Captain Cold beats up Digger for freeing Zoom, then Digger explains to him the importance of the Entity's message. Later, Captain Boomerang is contacted once again by the Entity, who tells him that he must complete his task, prompting Digger to travel to
Star City forest, which by now is surrounded by a white barrier. While there, Captain Boomerang discovers that he is the only one who can enter the forest. Within the forest, Captain Boomerang finds Dawn and throws a boomerang at her.
Hawk, however, fails to catch the boomerang and instead, the boomerang is caught by Deadman, who ended up dying in the process and Hawk is left to knock Captain Boomerang unconscious. After the Entity proclaims Captain Boomerang has completed his task, and his life is restored to him, the Entity reveals to them that the boomerang was part of a plan to free Hawk from his role as an avatar of war from the
Lords of Chaos: his act of saving Dawn would have broken the hold the Lords of Chaos have on Hawk and allow Hank to be true to himself. .George Harkness returns as Captain Boomerang in
The New 52, a 2011 reboot of the DC Comics universe. Captain Boomerang and a new character called
Yo-Yo join the Suicide Squad to replace the deceased members
Savant and Voltaic. He tells the team that he is the new field commander for the Suicide Squad, having been placed in that position by Amanda Waller. But this is further revealed to be a set-up orchestrated to give them a bargaining chip to bypass an armed Basilisk militia led by the sister of one of his victims. Realizing the trap, Boomerang attempts to use a detonator he was given that is supposed to be connected to the microbombs in each Squad member's skin. It fails to function, and Deadshot mocks him for thinking that Waller would trust him with that kind of power before shooting his hand.
Owen Mercer At the beginning of the 2004
Identity Crisis storyline, "Digger" Harkness a.k.a. Captain Boomerang found himself an obsolete villain in the modern world of supervillains. Regularly going up to the supervillain satellite looking for jobs, asking favors from the
Calculator, he was at the end of his rope looking for a job to put him on the map again. During this time he felt it was finally time to reach out to the son he never raised,
Owen Mercer. Before Harkness's death, the two bonded. Taking up his father's legacy, he became the second Captain Boomerang.
Captain Cold, brother to
Golden Glider (who was believed to be Owen's mother), took Owen in as one of the
Rogues. Though Owen initially had no real attachment to the Rogues (and even voiced various, albeit short, opinions out loud), he grew to enjoy the purpose and sense of family the team offered after finding that his father's body had been stolen for use in a lab (which was later revealed to be part of a plan to get memories from Harkness). Around this time the
Rogue War storyline began, in which the "reformed" Rogues fought the Rogues under Captain Cold. Ashley Zolomon is told by Harkness himself (he is briefly revived by the "reformed" Rogues as part of an experiment) that Golden Glider is not Owen's real mother. Later, it is revealed in
Flash #225 (January 2006) that Meloni Thawne is the mother of Owen Harkness, formerly Owen Mercer, the new Captain Boomerang, having conceived him by the original Boomerang while he was trapped in the 30th century. During the 2005–2006
Infinite Crisis storyline, Owen was part of
Alexander Luthor Jr.'s
group of villains. He, Captain Cold, and
Mirror Master were sent to guard a factory against the
Outsiders, under the command of
Deathstroke (who was actually
Arsenal in disguise). When the ensuing battle between Outsiders and Rogues destroyed the machinery in the factory, the Rogues and other villains would not help in the fight at all and then at the explosion, he is saved by the Outsiders, while the Rogues left them at the base to blow up. He is then turned over to the authorities off-panel. During the
52 series, Owen is part of a
Suicide Squad sent by
Amanda Waller to attack
Black Adam. In the 2006
One Year Later storyline, Owen is imprisoned in
Iron Heights Penitentiary. There he finds himself being the cellmate of
Black Lightning, who was arrested for a murder that Deathstroke committed. Owen has also developed a close friendship with Supergirl,
Kara Zor-El. Owen is killed by his father, the first Captain Boomerang, and resurrected as a Black Lantern shortly afterward. Owen Mercer is resurrected following
The New 52 and
DC Rebirth relaunches, which rebooted the continuity of the DC universe. ==Powers and abilities==