What follows is the mildest of spoilers for Batman v Superman: Dawn of Justice.
The Dawn of Justice in the movie's title comes from the introduction of the members of the Justice League, DC's big team of their heavy hitters, the Justice League will be getting their own movie in 2017. Batman, Superman and Wonder Woman all appear as actual characters in the movie but the remaining three members of the team - Cyborg, The Flash and Aquaman - are relegated (mostly) to appearing as video files on a computer. Weirdly, the video files come from Lex Luthor, who has not only been tracking metahumans in the world but has also gone to the trouble of giving each their superhero name and creating their logos for them. He's not just an evil genius, he's also a branding expert!
So how do each of these nascent superheroes look? Lets' review em, one by one.
Aquaman: The video comes from two cameras, underwater subs both. One camera approaches a sunken ship (I think) and within its fractured hull two eyes glow in the green nightvision. Aquaman, fierce looking, swims forward with a trident and uses it to destroy the camera. The secondary camera picks up as he swims away, seemingly so fast that he can break the sound barrier (I have no scientific opinion on this).
You've seen Aquaman, and he looks like what you've seen here. The one big problem with this sequence? Actor Jason Momoa is so clearly holding his breath it's kind of funny. Aquaman can breathe underwater, and I hope that this gets fixed by the time his solo movie debuts - you can't have an Aquaman film where your hero looks like he's got a huge bong rip being held in all the time.
The Flash: This character appears twice, once in a dream sequence that will make no sense to perhaps 90% of the audience. On the surveillance tapes that Lex has Barry Allen shows up, long hair pulled up, in a convenience store shopping for milk. It turns out the store he's in is being robbed, and Barry quickly runs across the store and knocks out the robber. Here's the thing: when he activates his power the electricity in the store blows out, shelves get knocked over and the lighting fixtures explode. I am guessing the robber would have nabbed $50; Barry causes hundreds more in damage.
His other appearance is in a confusing and poorly sound mixed dream; he comes leaping out of a wormhole/rip in space-time/Boom Tube wearing some sort of complicated armor that peels away from his face. He's from the future and he's here to warn Batman that he was right about Superman all along. It's very hard to hear and he's not immediately recognizable. His future costume looks overly complicated.
It's hard to judge The Flash here because they give us very little. This Barry Allen is just a dude - there's plenty of room for future movies to define who he is better. And the explosive nature of his powers seems like something that will have to get dropped pretty much immediately - it's just a nonsensical approach.
Cyborg: The longest of the video introductions is also the least coherent and most disturbing. We watch through STAR Lab cameras as Dr. Silas Stone reveals that his cork board has been repurposed to hold the severed upper torso of a young man (it's his son, but I don't recall if the sequence makes this clear). It's a pretty creepy sight, and Dr. Stone talks about how he has been trying to keep the stub of a human alive, and how he is failing. There are a couple of cuts as the tape leaps forward in time, and then suddenly Stone has a weird box, one that is made up of other, smaller boxes that pulse and writhe. It could be a Mother Box, although it doesn't immediately remind me of one. Anyway, Stone says that he will be abandoning clinical protocol and will be using this box, the property of the US government, as the next step. He carries the thing over (it looks really silly, to be honest) and attaches it to the horrifically maimed body. The kid on the cork board starts screaming as the box attaches itself to him and begins growing arms and legs. This goes on just long enough to really make your skin crawl.
Ray Fisher is playing Cyborg, but he has nothing to do here except scream. It's hard to get any sort of sense of what this character could be like in the eventual Justice League movie.
Wonder Woman: She's in the files - Lex has a picture from 1918 that was obviously taken on the set of the upcoming solo movie, as Chris Pine is in it - but she's also in the movie itself. As Diana Prince she's the sneaky equal to spying Bruce Wayne, and Gal Gadot holds her own well enough opposite Ben Affleck. When she puts on her costume at the end things get pretty good. Wonder Woman is able to clash her bracelets together to create a wave of force that knocks Doomsday back, and she has a sword that is able to cut through his Kryptonian flesh (I'm assuming because it is magic and Kryptonians are susceptible to magic attacks). She eventually whips out the lasso and uses it to bind Doomsday for the final blow, and it looks quite a bit like a lightsaber blade that snakes around.
Gadot is good, and Wonder Woman seems like a character who can work on her own. I would have liked to see her interact with Batman and Superman more (or with Superman at all), but playing a character without an organic place in the story Gadot still acquits herself well.
Batman: One of the few successes in BvS is Batman, and his personal arc. The character at the beginning of the film wouldn't even join the Justice League, but by the end he is the guy forming it. It works as presented, and I think Affleck will make for an able leader of the group. Batman's the highlight of BvS, and I suspect the same will be true in Justice League.