During December 2010, Kid Flash's relationship with Artemis reached a new low as she struggled to maintain her secrets. Eventually, Artemis, Superboy and Miss Martian were able to reveal secrets they had been keeping, allowing the Team to deal a major defeat to those who sought to manipulate them. When the entire Justice League came under the Light's control, the Team rallied to find a cure and rescued their mentors.
Wally was elated that Red Arrow finally joined the Team, but surprised at Artemis's reaction. Green Arrow gave them a mission to follow Sportsmaster, for which Artemis volunteered. On the way to New Orleans, Wally told Artemis he considered her part of the Team; he was just happy for Red Arrow because they go way back. But Artemis had, in his eyes, already proven herself.
They found Sportsmaster easy enough. He had rented a boat, so they followed him. Wally rode his bike along the river. When he finally arrived at the location, he saw Roy and Artemis were fighting with Cheshire; he cannonballed into her and stole her sai. Red Arrow went after Sportsmaster, while Wally and Artemis had to fend off Cheshire. They allowed her to escape, after Artemis planted a tracer on her.
They reviewed their case; Kid Flash defended Artemis from blame that she should have stayed in the Bio-Ship. He trusted her to track Cheshire, but she gave him the assignment instead.
He followed it with Aqualad, but found it on a train, not on Cheshire. Red Arrow contacted them to meet him in New Orleans; Kaldur sent Kid Flash ahead.
New Orleans December 5, 22:18CST
When he got to Red Arrow's location, Kid Flash attacked Cheshire, allowing Artemis the opportunity to investigate what went on in the back of the building. In the middle of the fight, Cheshire suddenly turned to ice and disappeared. All the other villains were gone.
They returned home, where Red Arrow was quick to blame Artemis for the failure. She defended herself, but he didn't buy it. Kid Flash spoke in her defense as well, but then, Red Arrow showed him her tracer: she had deliberately shot a tracer at a passing train to send them in the wrong direction. Kid Flash accused her of insecurity, thinking Red Arrow's place in the Team caused her to want to solve the case solo. She didn't give a satisfying answer, which clinched it for him. He threw the sai at her feet, and added the tracer to his collection instead.
Wally was hanging at the Cave, but everyone was gone. He checked with Red Tornado, but Batman hadn't given any missions. He contacted Dick, and confronted him with his finds. Robin had lied to the others about a secret mission from Batman, but confided with Wally that it was about Haly's Circus. Knowing his backstory, Wally thought he could have been a great addition to the mission. But Dick wouldn't have it; he didn't like his judgment being called into question. Wally replied that that was what best friends were for.
The Team watched the induction of five new Justice Leaguers, including Red Arrow. They had to explain a lot to their newest member, Rocket, who was unfamiliar with everything that had happened the past weeks. In the middle of his explanation, Robin was interrupted by his computer. Cheshire was sighted boarding a plane in Asheville.
They traced the plane to the Smokeys, and found it crashed in a valley. When they investigated, Riddler revealed it was an ambush; he put up a force field around them to prevent escape, and sent his associates in. Zatanna created a snowstorm, and each picked their target. Kid Flash took out multiple henchmen by running into them. When the battle was over, Riddler, Mammoth and Shimmer were arrested. They recovered a case Cheshire was carrying.
The Team brought the case to Batman, who was going to study it. But as soon as he and the other Leaguers left, the Team discussed the trap. Someone tipped off the villains.
After being contacted ultrasonically by Lex Luthor, Superboy admitted to the Team that only half his DNA was human, he had been using shields, and that Luthor wanted him to go to Santa Prisca. Hearing this, Artemis came clean as well. She revealed her family secrets, that her mother was Huntress, her father Sportsmaster and her sister Cheshire. Suddenly, it all made sense to Kid Flash; why she was so secretive, and why she dropped the ball in New Orleans. After Robin explained to her that he had found out, but thought it didn't matter, Kid Flash walked beside her to support her.
After Miss Martian revealed she was being blackmailed by Queen Bee, they formed a plan.
Kid Flash was part of the back-up crew, called in if the fight broke loose. He first attacked Cheshire, and then tried to run at Sportsmaster. His attack was parried, however, and Sportsmaster threw him into a tree. By the time he'd recovered, Artemis had defeated her father, and gave Kid Flash his mask as a souvenir.
Having returned from Santa Prisca, the Team learned from Batman that Red Arrow was the mole and a clone, and that the real Roy Harper was likely dead. Wally was shocked, and no one could believe it. As soon as Batman left, Red Tornado powered down. Kid Flash discovered Tornado held one of the chips they had confiscated off Cheshire. Kid Flash, Zatanna and Rocket stayed with Robin to try and fix Red, while the others went looking for Red Arrow.
Zatanna suggested moving Tornado's consciousness into the "John Smith" android. While the transfer was completing, Black Canary arrived, and attacked them. Kid Flash was knocked back; Robin and Rocket defeated her. Red Tornado told them to abandon the Cave, and on their way to the rest of the Team, he explained the entire League had been put under mind control by the Light.
The Team traveled to the Watchtower in the Bio-Ship and entered it clandestinely by breaching a hole in the side. Breaking into tactical teams, the Team split up. Artemis and Kid Flash ambushed Plastic Man and gave him cure-tech. Moving on, they soon found themselves fighting for their lives against Flash, Green Arrow and Aquaman in the hangar, requiring them to call in backup from the rest of the Team. Aqualad defeated them by opening and then closing the air lock, causing the Leaguers to hit the air-lock doors.