The Flash, after years of development, was finally released in theaters and offered a loose adaptation of the Flashpoint story from the comics. Following Barry Allen as he travels back in time to save his mom from being murdered, only to find out that he has messed up the future even more, the comic and the film share the same story, but it's the execution of it all that really stands out.
Flashpoint is easily one of the Flash's most iconic stories. It offered many new insights into the DC universe, and it surely is one of Barry Allen's most defining stories. In the same way, the live-action film too is a defining moment for this version of Barry Allen, and it added changes to this already classic story that kept the same message but added a few new elements to it.
Ezra Miller's The Flash adds many new elements and changes to the Flashpoint story from the comics
Written by Geoff Johns, Flashpoint saw Barry Allen travel back to the past and save his mother from being murdered by Reverse-Flash, aka Eobard Thawne. He does this by running so fast that he makes it to the day his mom was about to be murdered and distracts Thawne, which causes the future to be completely changed.
Upon returning, Barry is finally reunited with his mother, but he notices that he has made the timeline even worse. For starters, he doesn't possess any superpowers, and Themyscira and Atlantis are on the brink of war, which puts the existence of the planet at stake. Seeking the help of Batman, he realizes that it was Bruce Wayne who died in his parents' place in the timeline and that Thomas Wayne would take up the mantle of Batman while Martha Wayne would become the Joker.
Superman also doesn't exist in the world, as his escape pod from Krypton crashed on Earth and was intercepted by the American government, which trapped Kal-El and experimented on him. The Flashpoint story then concludes with Thomas Wayne recreating the accident that gave Barry his powers and him fighting a climactic battle with Reverse-Flash, who gets killed by Batman. This then prompts Barry to run back in time and let his mom be murdered so that the timeline can return to normal.
The Flash has a similar concept, but a lot of the aesthetics are changed here. For starters, we never see Reverse-Flash kill Barry's mom in the movie, even though the director has confirmed that it is the villain who murders his mom in the film. Rather, Barry prevents his mother's death in a completely different way by traveling back in time and making sure that she isn't left home alone.
On the other hand, instead of just having one Barry, we get two Barrys in the movie—one being the primary Barry and the other being a younger version of him whose timeline our hero finds himself in after being thrown into it by the Dark Flash, who becomes the villain of the film as well.
The Batman over here isn't Thomas Wayne as well, which many already know, but rather Thomas Wayne in this story is replaced by Michael Keaton's Batman, who explains how changing the past can lead to different realities overlapping each other, hence explaining why he is there.
The Flash also substitutes Kal-El here for Supergirl, who has the same story as him from the Flashpoint comics, and also replaces the war between Themyscira and Atlantis with Zod's invasion of Earth, which fits in with the universe of the DCEU. These are, however, cosmetic changes, as the film still ends with Barry going back in time to let his mom die and save the timeline.
This effectively sets up the new DC Universe as well, in the same way that the original Flashpoint comic was used to establish the New 52 line of comics. The differences are there, and they are pretty significant, but it was pretty clear that director Andy Muschietti very much wanted to honor the themes of the comic.
The Flash is playing in theaters right now.