The Flash director Andy Muschietti recently shared why he was so confident Michael Keaton would agree to return as Batman in the upcoming DC Universe movie.

In an interview with io9, Muschietti revealed that there was no backup plan should Keaton refuse to reprise his role as Tim Burton's Dark Knight. "No, no, no, no. We were, of course, [filled with] blind confidence that you have when you’re developing a movie and you get excited about ideas like this," the director explained. "[It] just pushes you forward. We were all excited believing that having Michael Keaton as Batman would be a great thing in the movie. And also, I think we all believed that he would be excited about it. And he was."

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Keaton first played Bruce Wayne/Batman in Burton's 1989 film, Batman, and returned to the role for the 1992 sequel, Batman Returns. After Burton stepped down as director on Batman Forever, Keaton also departed the series with Val Kilmer selected to star as the Caped Crusader in the 1995 film. George Clooney then replaced Kilmer as Batman for 1997's Batman & Robin, which was the last entry in the Burton/Schumacher film series.

When Muschietti and his producing partner/sister Barbara Muschietti took Keaton out to lunch to pitch him The Flash, it had been almost 30 years since the actor had last played Batman. The Muschiettis admitted to io9 that they were nervously excited to meet with Keaton because, in their minds, The Flash wouldn't work without Keaton's Batman. "And in moments like that you just have to lean in," Barbara said. "As we sat with him at a lovely lunch, we told him that we couldn’t make the movie without him. And he boarded the train."

A Tale of Two Caped Crusaders

Keaton's Batman will exist in the alternate timeline Barry Allen/The Flash (Ezra Miller) creates after traveling back in time to prevent his mother's murder. However, Keaton will not be the only Caped Crusader suiting up in the superhero film as Ben Affleck will be reprising his role as the DC Extended Universe version of Batman. According to the actor, The Flash features "maybe my favorite scenes in terms of Batman and the interpretation of Batman that I have done." He added that working on The Flash was "really fun and really, really satisfying and encouraging" and left him thinking that he had finally figured Batman out.

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The Flash's Box Office Tracking Indicates a Low Opening Weekend

At the time of writing, early box office estimates for The Flash has the DC superhero movie opening in the $70 million range. While that number is on the low end, box office insiders have noted that The Flash's hold once it opens will be more important in determining the film's success than its opening weekend gross. For instance, 2018's Aquaman opened to just $67.8 million, but managed to leg out to $335 million domestically and $1.148 million globally. There are also two weeks left until The Flash releases, meaning there is still plenty of time for the film's opening weekend estimates to improve.

The Flash opens in theaters on June 16.

Source: io9