In an effort to catch up with Marvel's Cinematic Universe, DC's own version, which started with the standalone Man Of Steel, only featuring Superman, had decided to cram their follow-up, Batman v Superman, with as many cameos of Justice League members the film's running time and story would allow.
Of course this might be a smart move because Marvel has had a good head start on DC. We'll be getting Batman, played by Ben Affleck, and Superman, played by Henry Cavill, in the main roles, and, judging by the trailers, Gal Gadot's Wonder Woman is getting a minor supporting part. Aquaman and the Flash will probably zoom in and out just enough to excite audiences.
There has been no word yet on how Aquaman, who will be played by Game of Thrones' Jason Momoa, will appear in the movie, but details have emerged of what form the sequence of The Flash will look like.
WB has confirmed that the speedster, played by Ezra Miller, will be appearing in a dream to Batman. In this scene, the Flash will be giving Bruce Wayne a cryptic warning message of sorts.
Of course, this dream unhinges the Dark Knight, who is unsure of how real this message is. After all, as it is seen in the trailers and with details released by the WB, it is clear that Batman is wary of the super-powered beings that have emerged in his world, and he is, in fact, on a crusade against Superman.
The Flash is known in the comics and among fans as someone who could time travel and effectively cause ripples in reality, so it might be possible that the Flash may be more than just a being who appears to Bruce in his sleep. Why else would he appear in Batman's dream? -- unless, for some reason, the Flash appears as Barry Allen in the movie, and he and Bruce have met before.
All we have is speculation from the little that is known right now, so we'll just have to wait when Batman v Superman premieres on March 25.