On paper, the animated movie hits the same major beats as the comic event, but the way it delivers them is a different animal. I’ve read Geoff Johns’ 'Flashpoint' more times than I can count, and the film 'Justice League: The Flashpoint Paradox' keeps the core: Barry Allen’s grief-driven decision to change the past, the resulting fractured timeline where Thomas Wayne is Batman and Martha Wayne becomes something monstrous, and the catastrophic war between Atlantis and Themyscira. Those iconic images and the emotional heart — Barry wrestling with guilt over his mother — are preserved, and that makes the adaptation satisfying in a nostalgic, punchy way.
Where the movie diverges is in scope and depth. The comic event sprawls across dozens of tie-in miniseries that deepen characters like Cyborg, show how the altered world functions, and offer lots of smaller tragic moments. The film condenses or outright omits many of those threads: some side plots are collapsed, motivations are streamlined, and a few characters get less screen time than they deserve. Also, specific reveals and sequences are rearranged to fit a tighter runtime; the film is considerably more direct and violent, but it’s less encyclopedic than the comics.
All that said, I love both versions for different reasons. The comic is messy, sprawling, and devastating in layers; the film is furious, focused, and emotionally immediate. If you want the full blood-and-bones Flashpoint experience read the comics, but if you want a potent, cinematic take that nails the emotional center, the animated film delivers — and it left me buzzing for days.