Zack Snyder Reveals Why Grant Gustin Wasn't Cast as The Flash in 'Justice League'
“I just don’t think it was a good fit. I’m very strict with this universe, and I just don’t see a version where… that (tone is) not our world,” Zack told the New York Daily News.
“Even if Grant Gustin is my favorite guy in the world and he’s very good, we made a commitment to the multiverse (idea), so it’s just not a thing that’s possible,” he continued.
Ezra Miller landed the role of The Flash in the Justice League movies.