With all its 3D pyrotechnics and superhuman smackdowns, you wouldn't mistake Marvel Studios's Iron Man franchise for a romantic comedy. But after teaming up with his fellow superheroes in last year's Avengers extravaganza, the close bonds between Robert Downey Jnr's Tony Stark and Gwyneth Paltrow's Pepper Potts are very much at the forefront of the cinematic version of Shellhead's third solo adventure, in which Lethal Weapon screenwriter Shane Black replaces Jon Favreau in the director's chair.
"Shane's first notes to me about what we needed to put in the movie was that Iron Man on many levels was actually a rom-com," says Drew Pearce, who co-wrote Iron Man 3 with Black. "There's almost something Wilder-esque about Pepper and Tony's banter in the first movie and it's very rare that you get two actors that can do that. Gwyneth and Robert have that relationship and she's probably the only one who can keep up with him."
"The temptation will always be there to say 'do you really need these jokes'?" continues Black. "But you do because you need to set up who these people are before you start throwing them through the air."
Apart from being Tony's full-time romantic and business partner, Pepper is much more involved in the action in Iron Man 3. "Part of the fun of doing these films is that she keeps evolving," says Paltrow, who had not been familiar with the character first introduced in 1963.
"I hadn't heard of Iron Man until Jon Favreau called me because I didn't grow up reading comics. When the first Iron Man came about, there was no actual script to begin with so I ended up flying blind. I didn't know anything about the comics or the movie we were going to do but Robert and Jon talked me into doing it.
"I never would have thought of myself as being in a comic book movie but now I'm so happy that it's basically been my job for the last six years."
Having just seen it the previous night with her husband, Coldplay singer Chris Martin, and their two children, Apple and Moses, Paltrow was pleasantly surprised by the finished film. "We all saw it last night with my kids and all their friends," she says. "Everybody loved it, including me. When I'm on set I find it difficult to follow the plot on paper when it comes to who is getting shot or who is good or bad."
Iron Man 3 also features another significant female protagonist in Rebecca Hall's Maya Hansen. The leading biotechnologist appeared in the 2006 storyline Extremis, upon which the script is partly based.
"I liked that she was written as being every bit as intelligent as Tony and that she was another female in this world who wasn't merely engaging in a bitch-fight with Pepper over him," says Hall.
"She has a kind of driven integrity that comes from wanting to do some sort of good for humanity but has got compromised along the way.
"She also seemed to be that very American kind of dry and sassy character, who felt very
pulpy to me.
"There's something interesting about playing a genius. She's not very polite or socially acceptable at times and is quite tunnel-visioned to her detriment."
Pitting the Armoured Avenger against Sir Ben Kingsley's sinister Mandarin who claims responsibility for a campaign of mysterious explosions, Iron Man 3's plot eerily struck a little too close to home after the Boston Marathon bombing, which occurred just a few days before the film's London premiere.
"If we'd used those elements for titillation, I would feel guilty but one of the things that I'm proud of is that we're tapping into the context of those kinds of ideas to bring a sense of reality to the film," says Pearce.
"But don't get me wrong, the last thing that our movie should be doing is becoming an analog of real-life events."
"We were working off of the first Iron Man and the villains in that were terrorists who were associated with a group known as the Ten Rings," adds Black.
"We wanted a kind of uber-terrorist, who would bring slightly more weight to what would otherwise be a silly comic book environment. The problem with comic books is that when you have a lot of violence in it, if it isn't grounded then it just trivialises it.
"I'm not saying that we should shoot something visceral like what happened in Boston but the fact that we say that this happens in the real world is a better approach to take for kids than just playing a video game where no one gets hurt."