13 killer spoilers, secrets and surprises from Kick-Ass

We've been waiting for Kick-Ass ever since it wowed San Diego Comic-Con last summer. Austin's South by Southwest film festival screened the film on its premiere night March 12.

Director Matthew Vaughn; Mark Millar, writer of the Kick-Ass comic book and screenplay; and stars Aaron Johnson, Chloe Moretz and Christopher Mintz-Plasse spoke to fans at a panel on March 13, and to a group of reporters at a press conference that afternoon.

Here are some secrets, easter eggs and spoilers to keep you excited until the film's April 16 release.

Kick-Ass is the ultimate fighting championship

In the world of Kick-Ass, teenager Dave Lizewski (Johnson) puts on a costume to become crime fighter Kick-Ass. His actions inspire other vigilantes such as Damon (Nicolas Cage) and Mindy Macready (Moretz) to follow suit (pun intended). Every single action scene is different. "Aaron had a different fighting style to Chloe, making it more Hong Kong style in the corridor sequence or Nic Cage doing it all in one take," Vaughn said at the press conference. "I thought, 'Let's just try and make each action scene get better and more interesting.'"

There's an 11-year-old girl beating up thugs!

Did we mention that little Mindy is only 11? She becomes Hit Girl and scores the most kills in the movie by far, even more than her father. "I basically did almost everything except for running up walls and doing insane back handsprings in the middle of the air," Moretz said at the press conference. "Basically, all the shooting and knives and swords and stuff was me."

Don't worry, Hit Girl was safe

Okay, parents, don't send in your hate mail. That preteen actress was perfectly safe doing high-action wirework. "It was completely safe," Moretz said at the press conference. "So safe to where if I got a speck of dust in my eye, they would freak out." To be clear, Vaughn added that everyone was safe, not just the kids. "We have safe sets, whether it's an 11-year-old or a 50-year-old," Vaughn said at the press conference. "She was just part of the team."

It's the greatest hits of superhero movies

Remember the scene in Spider-Man where Peter Parker tests out his new powers on the rooftop? Kick-Ass tries it without the benefit of webbing and genetically enhanced strength. "Spider-Man we tried to do shot by shot, but we couldn't afford to put a crane up there," Vaughn said during the panel. "Literally every scene we were taking things from movies we'd seen before. The Mist-mobile is literally from the Tim Burton Batman. The jetpack is actually meant to be the X-wing fighter shooting the Death Star." Yes, that's a Star Wars reference, too.

You don't know how this ends

Even if you read the Kick-Ass comic book, the movie will surprise you. The climax of the film is different from the final issues of the comic series. "The episodic nature of comics meant I had to have an eight-act story, had to have reveals and twists that would have messed up the nature of the film," Millar said during the panel. "Big Daddy's story in the comic book ... would've ruined the movie. Likewise, the jetpack scene wouldn't have worked in the comic. It was only two or three real diversions it took, but it was just necessary. Whenever somebody slavishly adapts a graphic novel, it can be tedious."

There's a comic book in it

Kick-Ass is such a loving homage to comic books and superheroes, they actually put a comic book in the movie. The film portrays Big Daddy/Damon Macready's history in a two-dimensional comic book that comes to life. Like Kill Bill's anime sequence, only more panel-y. "The idea was it was just too expensive to start trying to make Nic look young," Vaughn said during the press conference. "I hate having different actors play the role, so we thought it'd be a cool idea. I think it paid off. We only finished that about two, three weeks ago."

Look for Hellboy, Runaways and the Spirit in Kick-Ass

There are comic-book references buried in the scenes of Kick-Ass, too. Look at the standees in the comic-book store that Dave frequents. Listen for the name drop of Hellboy's creator. Definitely check the movie theater marquee in the beginning. "They were just our mates," Millar said in the press conference. "Brian K. Vaughan, who does Runaways, is a good pal of mine, and Mike Mignola is a guy that we've known for years. It was funny, in that comic store, all the books that were up front were all the people we like, and all the guys we hate, we put them in the back."

Brad Pitt is Kick-Ass' real-life sidekick

Kick-Ass protects the innocent, but who can save Kick-Ass from Hollywood? Megastar Brad Pitt helped produce the film, and Vaughn turned to him for muscle when he financed the film independently of studios. "Brad was my anchor of how everything worked in America," Vaughn said in the press conference. "When I realized I was sort of declaring war, I thought I might as well have an ally that's like a 10,000-pound gorilla, which he can be in a good way. I sent him the script. He was one of the first people to read the script, and he just loved it. He said, 'Whatever you need to get this thing made, let's just do it.'"

Nic Cage finally gets to play a real superhero

You know Nicolas Cage is obsessed with comic books. He almost played Superman in a '90s movie, and he even named his son Kal-el. Sure, he got to play Ghost Rider with a CGI flaming skull, but putting on a rubber suit to beat up bad guys is the real thing. "Comic books are a very big deal to the guy," Vaughn said in the panel. "He loved it, but the helmet is actually more like from Phantom of the Paradise."

And he did Adam West

Cage also affected an odd accent as Damon Macready, modeled after TV's Batman, Adam West. "The only thing about Dark Knight that drove me nuts was the stupid voice," Vaughn said in the panel. "So we'll have a silly voice as well, but we'll do it in a way that was actually supposed to be silly."

McLovin is the Jack Nicholson of Kick-Ass

You may not have heard of the film's star, Aaron Johnson, but you know Christopher Mintz-Plasse as McLovin. He plays Red Mist, another costumed kid character. Perhaps he's the film's marquee name, like Nicholson in the original Batman. He even gets to say one of Nicholson's key catch phrases. "I definitely YouTubed Jack Nicholson's clip from the original Batman and tried to do the best," Mintz-Plasse said. "I'm not as good as Jack Nicholson. I'm just going to admit that to you guys right now. It's a kid looking up to Jack Nicholson."

You won't believe what they faked in Kick-Ass

It's no surprise that a comic-book superhero movie has a lot of visual effects, but aside from the kids flying a jetpack, you won't even notice what was CGI. "I think there's about 820 visual effects in the film," Vaughn said during the panel. "Hopefully most of them we wouldn't have noticed. We didn't shoot it in New York. We shot mostly in London, so the majority of effects were wire removal, putting in the blood, putting in New York, and obviously we couldn't put these two on a jetpack, so that was CG. All the fights were done in camera. Wire removal sometimes, but not much."

If you like this, buy lots of tickets so we can see the sequel!

Comic-book author and screenplay adapter Mark Millar is already thinking of plans for the further adventures of Kick-Ass and Hit Girl. You won't believe the new supervillain he's planning. Even if you hate Kick-Ass, you'll want to meet the sequel's new cast. "We're talking about another villain as well," Millar said during the press conference. "I'm [deciding] somewhere between the Motherf--ker and the C--t. That's the two names I've got, but it's better than the Joker, isn't it?"

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