George "Digger" Harkness, aka The Suicide Squad's Captain Boomerang, receives an ignoble death early on in James Gunn's movie, but being dead won't necessarily prevent his return in future films, since it certainly didn't in the comics. The infamous Flash Rogue and member of the Suicide Squad known for his aim and trick boomerangs met his end during the controversial Identity Crisis. Harkness returned to life during DC's Blackest Night, and remains a fixture in ongoing stories.
Created by John Broome and Carmine Infantino in Flash #117, the Australian criminal's crime sprees were constantly thwarted by Barry Allen, the second Flash. Eventually Captain Boomerang was recruited for Amanda Waller's Task Force X where, despite his longevity, he was unpopular and distrusted by his teammates due to his provocative attitude. Although he enjoyed a brief stint impersonating the Mirror Master, Digger remained with the Suicide Squad until they disbanded. He met his death in 2004's Identity Crisis when he was hired to kill Jack Drake, the father of then-Robin Tim Drake, only to be double-crossed by his employer, who gave Jack just enough notice to fight back. Although both men perished, Digger's legacy lived on in his son Owen Mercer, who he had reconciled with before his death, and who donned the mantle of Captain Boomerang.
Despite being briefly revived by the original Trickster during the Rogue War storyline, Captain Boomerang made his official return during 2008's Blackest Night storyline. In this huge event, Green Lantern villain the Black Hand resurrected a host of dead heroes and villains to serve him as an army of intelligent zombies. Revived as a member of the Black Lantern Corps in Blackest Night: Batman #3, Digger and other Batman-related supporting characters or villains attempt to kill and convert Batman and Red Robin, the current aliases of Dick Grayson and Tim Drake. Digger played a bigger role in the Blackest Night: Flash series by Geoff Johns and Scott Kolins as he joins other reanimated Flash villains who attack both the young and older Rogues in hopes of turning them into Black Lanterns as well.
Harkness later persuaded his son to lure innocent people to their deaths in the hope of bringing him fully back to life, and Owen is tragically killed (and turned into a Black Lantern) when the villainous Rogues take revenge for his murder of women and children, feeding him to his father. Captain Boomerang was among twelve heroes and villains resurrected by the White Lantern at the end of Blackest Night, later imprisoned for his crimes in Iron Heights Penitentiary. Eventually escaping, Captain Boomerang returned to his previous ways and was once again drafted into the Suicide Squad, occasionally crossing paths with old foes like the Flash.
While the extensive Green Lantern mythos is unlikely to bring back Digger in the movies, raising him from the dead as a killer zombie in some other way isn't unlikely, and nor is his misguided son taking up his title. Actor Jai Courtney has expressed interest in a spin-off movie or TV show, so despite his extravagant death at the start of The Suicide Squad, fans may yet see the villain return for more adventures. One of Captain Boomerang's most endearing traits is remaining a scoundrel even by the standards of other bad guys, and while The Suicide Squad gave him a memorable exit, Digger Harkness has never been one for respecting the rules - even the rules of life and death.