2016 is the year when superheroes stop being nice and start using each other as punching bags.

Before Marvel's "Civil War," Warner Bros. kicks things off with the long-awaited "Batman v Superman: Dawn of Justice." This film introduces Ben Affleck's Batman and marks the first time the two heroes have appeared together in a live-action movie. But Batman and Superman are just the tip of the iceberg, as this movie will pave the way for a much more ambitious DC Universe on the big screen.

Not sure why Batman and Superman are fighting? Having trouble keeping track of all of these characters? Not to worry. We're here to break down six important things you should know before watching "Batman v Superman."

WARNING: *minor spoilers ahead*

1. Not Everyone Is a Fan of Superman
"BvS" picks up in the aftermath of 2013's "Man of Steel." Superman (Henry Cavill) finds himself a controversial figure, to say the least. Though he saved the world from being wiped out by General Zod (Michael Shannon), the massive collateral damage to Metropolis has many questioning whether Superman is a blessing or curse to mankind. Many feel the world would be a safer place without Superman around, including a certain Dark Knight.

2. Batman Is Old(ish) and Cranky
Though the blockbuster will debut DC's newest cinematic version of Bruce Wayne, this Batman is already a grizzled veteran by the time the movie opens. "BvS" take cues from the classic graphic novel "The Dark Knight Returns," as Batman is compelled to come out of retirement and resume his war on crime, a war that now includes Superman. Batman is determined to take down the Man of Steel by any means necessary, even if it means donning a suit of armor and beating his opponent to death.

3. Lex Luthor and Doomsday Are the Real Enemy
It's pretty much a requirement in any superhero team-up that two heroes fight before putting aside their differences to join forces for the greater good. "Batman v Superman" looks like it'll keep that trend alive. Lex Luthor (Jesse Eisenberg) is eager to take advantage of the public's mistrust of Superman. Based on the trailers, it appears that Luthor will harvest genetic material from the body of General Zod and use it to create the unstoppable monster Doomsday.

Fans have been waiting to see Doomsday in action ever since he killed Superman in the 1992 storyline, "The Death of Superman." By the size of the baddie, Supes will need all the help he can get in this fight.

4. Wonder Woman Is Badass
Though Batman and Superman are the main focus of this movie, look for Wonder Woman (Gal Gadot) to play a significant role as well. The trailers hint that there's a potential for romance between Bruce Wayne and Diana Prince, though Bruce doesn't seem to be aware of the fact that his would-be girlfriend is also an invulnerable Amazon princess. Apparently his detective skills are a little rusty.

Wonder Woman will likely be the voice of reason who convinces Batman and Superman to stop fighting each other and focus their attention on Luthor and Doomsday. Early reactions to Wonder Woman's first live-action appearance in a DC movie have been nothing but positive, which fans can't wait to see for themselves.

5. Other DC Characters Will Appear
Look for a number of other familiar faces to appear as DC expands its cinematic universe and builds towards the Justice League movies. Much of the "Man of Steel" supporting cast will return, including Lois Lane, Perry White and Martha Kent. Batman will be assisted by his faithful butler, Alfred (Jeremy Irons). It's believed that the film will also include small cameos from future Justice Leaguers like Aquaman (Jason Mamoa). Ezra Miller's Barry Allen, aka the Flash, will appear as well -- in a dream/vision thing to Bruce Wayne. Yup. In a dream. That's how they introduce a character who has never had a solo film before. That's happening.

6. It Sets the Stage for More DC Movies
All of this is in service to set up the DC-themed solo films for the rest of the Justice League characters. But the events of "BvS" will be picked up first in 2017's "Justice League," which could potentially bring another fan-favorite villain that audiences have been waiting to see on the big screen: Darkseid.

Also, look for a new series of solo Batman films that will build on the events of this movie and the upcoming "Suicide Squad" (pictured). With any luck, WB will soon have a superhero lineup to rival Marvel Studios at the box office.