As we now know, The Flash movie will include at least two iterations of Batman, but might we also see multiple other versions of Barry Allen? Recently, it had been officially confirmed that The Flash will see the returns of both Michael Keaton and Ben Affleck as Bruce Wayne, as the movie will establish a multiverse capable of featuring alternate versions of the same character. Seeing an opportunity, Eric Wallace -- the showrunner of the Arrowverse Flash series on The CW -- said ahead of Saturday's DC FanDome event that he's hoping to see his Flash make an appearance as well.

Of course, if Grant Gustin's Barry Allen from the Arrowverse series runs into Ezra Miller's take on the character in The Flash movie, it wouldn't be the first time the alternate Flashes have met. Previously, Miller made a surprise cameo appearance as the DCEU Flash in the televised crossover event Crisis on Infinite Earths. It was an exciting moment, but it was perhaps all too brief with fans wanting to see more of the two Flashes. Feeling that there's more mileage in a collaboration between Gustin and Miller, Wallace is now making the push to get Gustin into the movie.

"I would love to see Grant appear somewhere in their version of the film," Wallace explained. "Say I said, 'You know what? I'll give you a couple of weeks off easy now.' I don't know if they'll do that, but I'm putting it out there. Because I know Grant would be excited. I think he would have some fun."

If getting Grant Gustin into The Flash movie ultimately doesn't work out, Wallace says that there will still always remain an open invitation for Miller to come back to the Arrowverse. "I also told Ezra, with open arms, we would welcome him back," Wallace noted. "I would love to have him back for longer, for a full episode of The Flash TV Show, if we can somehow make it happen. Schedules are so tough. He's a very busy man. He has not just The Flash franchise, but other franchises too."

He adds, "So I don't know how possible it is, but I do know it's not impossible because we proved it in Crisis when we saw the two Flashes together. So I'm going to be hopeful and I'm going to put that energy out there. Hopefully someday sooner, rather than later, we will see those two Flashes of Ezra and Grant together and for anybody reading this article, I am happy to help accommodate in any way possible."

With the plot of the movie continuing to take shape, anything is possible with The Flash. The movie will also reportedly see the return of Gal Gadot as Wonder Woman, and with Affleck's involvement also confirmed, we could end up seeing a complete reunion of the Justice League. Even so, Keaton's reprisal of his Batman role from the original Tim Burton movies has fans especially excited, and the casting also made it clear that any fan favorite DC character from years past can potentially show up in the movie.

In any case, Wallace also says he will "literally be the first person in line to go see" the new Flash movie when it is released in theaters on June 3, 2022. Meanwhile, The CW's version of The Flash is set to premiere its seventh season in January 2021. This news comes to us from ComicBook.com.