While the pitched battle at the heart of DC's recently wrapped "Flash War" event may have set Barry Allen against Wally West, the most talked about reveal in the story was the return of another hero who once wore the Flash mantle.

And to hear writer Joshua Williamson talk about it, Bart Allen's role in the future of the franchise is only starting to speed up.

The teenage hero who's been known as Impulse, Kid Flash and briefly the Flash proper raced back into the DCU for the first time since the advent of the New 52 on "Flash War's" final page. And Williamson says that secret moment was long in the works for his tenure on the comic.

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"I cannot believe we kept it a secret. I can't believe no one knew," the writer told CBR during Comic-Con International. "The first time I brought up Bart in a meeting was when I got the job. My original document had everything in it, and they said 'No. You can't do all that.' But part of it at the time was that you can't just go to them and say 'I want this character just because.' You have to have a story and a plan for that character. I would say about every six months I would bring Bart up. Actually, it took the first year of me having the job to bring him up again, and then I'd bring him up again and again. It would always come back around."


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But Bart's return ended up being saved for a time when he'd have an impact on the broader DC Universe as Flash continues its long-simmering storyline. "I felt like the stars were finally aligning on big picture DC stuff so I could do this. And I remember when I put him in the script, I thought, 'Someone is going to stop me before this happens.' But I was able to pitch it and explain why it happens and how we'd move forward. Again, the stars just kind of aligned," Williamson noted. "I was in the office the week we went to print, and we kept it such a secret that some people in the office didn't know. Someone printed out a color copy of that final splash page, and I was even paranoid and said, 'Put that away!' I couldn't believe we kept it a secret that whole time."

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But now that the cat is out of the bag, Williamson can finally start telling the story Bart was meant to return for -- one that will have even more consequences than the one he just finished. "The event that is 'Flash War,' that was really the first battle in the war. There's a really big story we're building to," he said, noting villain Hunter Zolomon's warning that a threat too massive for either Barry Allen or Wally West to handle was coming soon. "These's a lot of unresolved stuff on purpose, because this is the opening battle of the big story we've got planned."

Flash #52 arrives this month from DC Comics.