The Kick-Ass movie and comic were being written at the same time - were you happy with how things turned out?
"Oh yeah, yeah it was very simple and the movie, Matthew [Vaughn] and I spent two days at his Wayne Manor on a country retreat before we started the screenplay. I'd only written the first five and a half issues of the comic, I'd only written up to Mindy's origin. I'd written half of issue five and half of issue six and obviously I had seven and eight to go. So Matthew was like, 'OK, what happens?' So we sat down and blocked out the screenplay and the scenes that were happening there and then, Matthew wrote out a skeleton screenplay that he passed onto Jane [Goldman], who then just made it sing."
Did it benefit from a woman's touch?
"I think the unsung hero has actually been Jane. The comic worked really well and I'm really happy with it but Jane just brought it to life. She made all the characters more than three-dimensional if that's possible. She made it light. My stuff can be quite harsh, but she brought a funny edge to it; a softer edge that made it just work. Everybody was laughing all the way through the cinema, which was great and would have probably not been the case if it was just me and Matthew."
What did you make of Nicolas Cage's Adam West impersonation as Big Daddy?
"I've always loved Nicholas Cage and I remember when he got announced as Big Daddy and being quite shocked when I went on internet sites, with people saying, 'Why Nicholas Cage?' I was like, 'Where have all the haters come from?' He doesn't just deliver a line, he invents a character around it too that ties in with it but also adds another level. The Adam West idea as Big Daddy was just genius, and also tiny little subtle things like Big Daddy having a normal moustache and then when he becomes Big Daddy he has a slightly larger moustache!"
Did you expect Hit-Girl to cause as much controversy as she did?
"Yes, yes absolutely. In fact I'd thought it would cause much more furore because it's so utterly shocking but I think it was because it was so charmingly done in the film that you were on her side and rooting for her all the way. You were seeing a little girl robbing and killing people and I think that was a testament to the acting and directing. But from the moment I first wrote her in the comic, and the first line I wrote coming out of her mouth was 'OK, you c**ts, lets see what you can do!' I just knew I'd stumbled on something."
Will the character change in the sequels?
"Yes. Well, the comic book and the movie obviously end in the same place and what you've got is essentially the world's greatest killer trying to pass herself off as a normal 12-year-old school girl. To me that suddenly seemed quite interesting and a movie like Unforgiven, where the world's greatest gunslinger has to hang up his gun, I liked the idea of doing that but with a little girl who has to turn her back on violence. The moment where she has to go back and help then becomes very powerful."
What can you tell us about the superhero movie you're directing in Scotland?
"It was quite nice actually as the pressure was off - it's quite a low-budget film and set in Scotland and there's nobody famous in it. So it's got all the ingredients of a non-superhero film. What's nice is nobody expects anything and I've got a track record with the writer, and my stuff's been adapted for film, but it's my first time directing anything and I'm going to learn as I go along. If it goes brilliantly then great and if I turns out to be rubbish then I'll hide it the best I can. I just love a new challenge."
When you bring a new comic out do you instantly get interest in making it into a film?
"Yes, it's crazy! Nemesis has just been picked up as a movie and we are hopefully going to start filming at the end of this year. When we first announced Nemesis my agent got a call from two producers that were massive fans of the book. It was just because of the buzz surrounding Kick Ass; guys were phoning up saying they were fans before it had even been released. I've been very lucky. As long as I play it carefully and as long as I only work with good guys then hopefully that will continue."
What's happening with Wanted 2? Is that still going ahead?
"I hear new stuff everyday. I hear stuff online, I hear stuff from Universal and I never quite know if it's going or not. Because Wanted was a bit of an anomaly, it came out and everybody was expecting it to make about $150 million and they ended up making $340 million so they were looking at making a sequel. I think they're regretting killing Angelina Jolie off, although that was a great scene. They tried to write a thing where she came back from the dead and Angelina was like, 'That's terrible!' They're trying something else. The guys at Universal are so nice and it's a great team and I'm involved as an executive producer. If anything happens it would be great."
Kick-Ass is available to buy on DVD and Blu-ray on September 6.
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