- "I didn't spend 5 years risking my life and my freedom to just be okay."
- —Kyle Reston on the gang's motives[src]
The Royal Flush Gang was actually a family of criminals whom Robert Queen had taken advantage of when he laid off their patriarch Derek Reston, one of 1,500 former employees who never received a severance package thanks to a loophole in his Union contract. This resulted in the Reston family losing their home shortly before the Queen's Gambit sank. 
To finance themselves and to ensure their family's financial security, they resorted to a three-year crime spree, originally operating with the intention of just stealing enough money so that they could live comfortably for the rest of their lives. They did, however, try to avoid hurting people whenever necessary. Whether this was out of a moral code of not wanting to harm innocents or simple common sense for not wanting additional heat from law enforcement is unknown. 
After Derek Reston's death, Teddy Reston became leader of the Royal Flush Gang and adopted his father's alias of King. The three remaining members of the family somehow managed to go back to their criminal enterprises following their arrest at the hands of the Star City Police Department, and eventually were defeated by the Flash while attempting to rob a bank in Keystone City.
- Derek Reston/King (leader;deceased)
Behind the scenes
- In DC comics, the Royal Flush Gang were criminals for hire, sometimes with an android Ace for muscle, who opposed the Justice League, and its individual members, on several occasions. In its later incarnation, it became another 'criminal octopus' similar to Intergang.