Obviously, this comes with a big, fat, hefty spoiler warning. Don't watch it if you have any intention of playing through Injustice 2 and experiencing it's dark vision of the DC universe for yourself, because this gives away literally everything.
The video here is a little over three hours long, and is a supercut of every single cutscene from NetherRealm's superhero fighter – from the opening scene with Kara Zor-El on Krypton, all the way up to the final showdown between Batman and Superman with a sprinkling of important fight scenes in-between. All put together like this, it works surprisingly well – and, who knows, it may actually be better than whatever Zack Snyder is currently beavering away on for the Justice League movie.
If you're a fan of a darker, more sinister interpretations of Superman, Batman, Wonder Woman and crew (and unfathomably elaborate body armor) it's certainly a compelling view and a daring interpretation of the material. If you object to the idea of beloved superheroes being total dicks to each other though, you may want to give it a pass.