Film Surprisingly Good, Albeit Flawed
I remember hearing about The Flash, but I wasn't really interested in it at the time. But when it came on HBO, I had nothing better to do at the time, so I said "Fuck it. Let's give it a shot". With that, I went in completely blind and with zero expectations... and I found myself pleasantly surprised. The movie was actually pretty enjoyable for the most part.
Now if you're familiar with The Flashpoint Paradox, then you know how this story goes: Flash goes back in time in an attempt to save his mother from her fated death and ends up making a bigger mess than he intended. However, there are a few twists in this version of the story. Instead of a war between Aquaman and Wonder Woman, General Zod ends up invading Earth earlier. Kara, Superman's cousin, gets sent to Earth and is captured by Russians. And Flash ends up meeting his past self. Oh, and Michael Keaton once again reprises his role as Batman, and does a pretty good job.
I did enjoy the interactions between the two Barry Allens and the twist that his past self ends up being the "Dark Flash". Instead of Professor Zoom, Barry's worst enemy is the living embodiment of all of his worst traits; his stubbornness, refusal to let things go, his insistence that he can fix everything. I just wish that "Dark Flash" had gotten more screen time. I get that it was intentional as to build up the hype surrounding the mystery of the character, but I would've liked if he had taunted Barry throughout the film. In fact, this ties into my overall complaint about the film: Aside from Batman and the Barry twins, some of the other characters were underutilized. Zod was there for no reason other than to be Kara's punching bag and I would've liked to see more interactions with Barry and Supergirl.
Overall, while I think the animated film did it better and this film has its share of flaws, it still managed to be enjoyable and is worth giving a watch.
Film Actually Quite Good, but Your Heart will Never Be the Same
Simply put, The Flash is a very good film. It has a rather weak start, with Batman and Wonder Woman and some not-very-good jokes abounding. But then we start digging into Barry's family, and that's when it starts to tug at your heartstrings. The sequence where Barry's mom dies is heartbreaking and incredibly well-acted and shot. Their relationship is just so tragic in general because you KNOW how it ends, and you can't help but feel for Barry.
Then we have both Barrys. We get some hilarious moments from the new Barry, and the old Barry's exasperation is also pretty funny. And we also get something that the ever-praised MCU lacks: someone not playing along with the quips. Someone who thinks that having fun while people are in danger and dying is not good. After Phase 4 of the MCU suffered from lacking that, I really enjoyed it. After that, Barry-2's character begins to develop and I start to empathize with him.
The time travel mechanics are fresh and interesting from different movies, so it's worth a watch for that alone.
And as we move into the second act, it gets better and better. The story of Barry during Zod's invasion brought tears to my eyes. Batman and Supergirl are as developed as their screentime allows, although I would have liked more. And then the badass Siberian breakout, Flash regains his powers, all of that's the standard cool superhero movie stuff.
And then... the climax. Hoo boy. At first it seems cliche, with the big CGI battle and the good guys winning... and then they don't. Batman and Supergirl's deaths tug at my heartstrings, and then the Flashes just can't save them. The big villain of it all is quite a tragic figure, and you can feel the pain of both our heroes. And in the end, when Barry puts the tomatoes back, you WILL cry. In the end, it's a very moving movie, albeit not without its flaws.