I just want to say before we start, FUCK YEAH! OK, now that I've got that out, let's talk about the trailer.
The trailer starts with Superman about to answer for his crimes from Man of Steel. I mean he did just kill half the city. But this is very good news. Like I mentioned in another article of mine, Batman v Superman will justify all the 'problems' in Man of Steel. Then we get to see what might spark Bruce Wayne's hatred for Superman. It turns out Superman, in his fight with Zod, actually destroyed a Wayne building and presumably everyone in it. This is later confirmed when we see Bruce reading a newspaper:
This looks like something that was written by the Joker. If it was him, he could be meaning that he failed the Bat Family (the death of Jason Todd, the loss of Barbra Gorden's legs). Whoever it was, probably knows Bruce Wayne was Batman and blames him for quitting. Then we see Bruce getting back on his feet as Batman. We see Alfred telling him that he is blinded by his rage. We see our first look at Alfred:
In that picture, you can see in the background a footage of Superman in action being played. This could be when Batman figures out his secret identity. After, it becomes kind of like how Batman returns in TDKR comic book. There is probably an older cop who is glad Batman's back, and a rookie who wants to stop him. We then see that Clark Kent doesn't agree with Batman's methods and tries to shut him down as through the media, but is shut off by Perry White. Afterwards, we just see Superman...being Superman. Next we see Lex Luthor's robot assistant/bodyguard, Mercy Graves:
This shows Luthor is manipulating the US senator, so basically he is turning the whole country against Superman. This next scene is very interesting:
Superman is kneeling before Lex Luthor when he didn't even kneel before zod! I doubt its because he is weakened somehow, because he doesn't look like he's in pain. So the only other thing is if Lex was threatening someone close to Superman (Martha Kent or Lois Lane) or maybe mind manipulation is involved (red kryptonite?) If it is mind manipulation, then that would make the fight between Superman and Batman more sense, because apparently Superman is the one that goes to challenge Batman. Also, Lex later goes on about 'man versus god' and 'night versus day' so that means that Lex knows the battle is going to happen. So Lex is probably manipulating Superman rather than Batman. He can't be the main antagonist if he doesn't have anything to do with the two greatest heroes of all time fighting. In the picture below, you can see that Lex Luthor is probably there for the fight between the heroes, because there is a constant light in the background (the bat-signal) and we saw in last year's comic-con that Batman turns on the signal to call Superman.
Full look at Mercy Graves and also we know General Zod's body is in that case. There have been rumours that his body is used to create DOOMSDAY! This is very possible. I think Lex would suggest his plan to the senator, senator approves, Lex teams up with US military and gains funding. He would use the funding to create Doomsday as a "contingency" plan against Superman. But when they actually unleash it (probably near the end of the movie) the public and the US senator realise that Doomsday is unstable and will kill anything and anyone. But Superman, Batman and Wonder Woman defeat it and gain the trust and respect of not only the US, but the whole world.
Probably the most interesting part of the trailer, that is definitely a Robin suit. Batman even says "20 years in Gotham, how many good guys are left?" Meaning that at least one protector of Gotham has died in the past. Whether it was Jason Todd or Dick Grayson or both, it could be reason Bruce Wayne stopped being the Batman. My guess is that in the picture above, its Jason Todd's suit because the graffiti says "the joke's on you", which is something the Joker would say and it was the Joker that killed Jason Todd.
This is probably not Aquaman, but possibly someone discovering something atlantean. Or it could be someone extracting a part of the destroyed world engine that was in the pacific. This next picture will send the whole timeline into confusion:
In the next picture we see possibly near the end of the movie when all the heroes team up and fight a common enemy:
Again, someone that causes that much damage is a Zod-level threat. So basically another possible Doomsday reference. Also there is another scene similar to that above shown earlier in the trailer:
So this is probably when Batman and Superman team up to defeat the common enemy, which will probably be the main 'muscle to the brains' villain.
Wonder Woman has her New 52 origins in the DC Extended Universe so this 'lightning' attack can be created by Wonder Woman, because she is the daughter of Zeus.
Our first look at kryptonite in the DC Extended Universe. Lex might give it to Batman and manipulate Batman to defeat Superman or just use it himself.
Everything else in the trailer is not that surprising, but its still cool. We see Batman and Superman fighting and what may possibly be Superman using his freeze/hurricane breath. So what do you guys think? Add anything I've missed in the comments below!