Michael Keaton's return to the big screen as Batman in DC's The Flash is already exciting enough, but could the film have even more surprises in store for fans? A new theory suggests that a major DC crossover involving Alan Moore's Watchmen could be in the works, and all of the clues are supposedly in Keaton's Batsuit.

Andy Muschietti, The Flash's director, recently shared a teaser image of the classic Keaton Batman costume, which showed the iconic black-and-yellow bat symbol across the chest. The color motif was expected, but the traces of blood on the left side corner of the insignia were not. Some say that the splatter could just have been included for aesthetic purposes, but what if it is hinting at something else?

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The first thing that comes to mind is the Watchmen, which famously used a logo of a yellow smiley face with blood smeared on it. If Muschietti's photo is actually a nod to Moore's group of vigilantes, that could mean that a crossover event between Ezra Miller's Flash, Keaton's Batman, and the members of the Watchmen is a possibility. Should DC want to make that happen, they could easily look to the comic books for inspiration.

In DC Universe: Rebirth #1, the yellow smiley face logo was found in Batman's Batcave, which foreshadowed the inevitable meeting between the heroes. A follow-up series named Doomsday Clock then had Batman and The Flash working together to investigate the button. The story not only linked the two heroes to the Watchmen, but it also introduced a whole scenario involving an alternate reality and time travel, which are both likely themes in the upcoming film considering it will be at least partially based on DC's famous Flashpoint storyline.

With Marvel making a cash-cow killing with its multiverse concept, it makes sense that DC is trying to explore its own multiverse as well, and there's no franchise more fitting to do that than with The Flash. He can run so fast that he is able to open up alternate realities, which is why Keaton's Batman from 1989 and Ben Affleck's Batman are even able to join forces with Miller's Flash in the film.

With that in mind, who's to say that other DC characters like the Watchmen, or even some other members of the Justice League, won't be making a surprise appearance? Fans will just have to wait for the film and find out for themselves.

The Flash is scheduled to be released in theaters on November 4, 2022.

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Source: Andy Muschietti/Instagram