Melissa McCarthy as Butt-Kicker, Jason Statham as Bumbler? How 'Spy' Director Paul Feig Casts Against Type

Paul Feig and Melissa McCarthy were laying the groundwork for Spy when the filmmaker directed the actress as a rough-and-tumble Boston cop in the 2013 summer hit The Heat. In the new espionage action-comedy now in theaters, McCarthy has graduated to full-blown fighting machine as a CIA-trained desk jockey who finally gets her chance to hit the field. The character is one of several of Spy’s sly against-type portayals.

“It’s the way that I cast,” Feig told us at the SXSW Film Festival, where Spy premiered. “So when I’m casting I go [not only], ‘Who would be funniest playing this role?’ But also, 'Who wouldn’t people expect to see to be doing something.’” Read on for what else he had to say about his five lead actors:

Melissa McCarthy

Robert Downey Jr., Dwayne Johnson, Arnold Schwarzenegger… Melissa McCarthy? The comic actress is on her way to becoming this summer’s most unlikely action star. As Susan Cooper, she wreaks havoc on rogues around the globe. “I like things that are about people you can relate to, and while I enjoy superhero movies and all that, I don’t relate to a superhero because he can do things I can’t do, and he looks better than I’ll ever look,” Feig said. “What I like is real-life people put in extraordinary situations… How do normal people step up to the occasion? Who has dormant skills that they suddenly get to use?” And much of what you see McCarthy using in Spy was done via her own hand-to-hand stuntwork. “She did a ton of it. She doesn’t like to use a stunt double unless it’s really dangerous. That knife fight, that’s her.”

Jason Statham

Feig wrote the role of tough-talking yet bumbling alpha spy Rick Ford with Jason Statham (Crank and Transporter) in mind. But he noted that when people read the script they assumed it was for a pratfalling comedian like Will Ferrell. “I’d love to do a movie with Will, but I didn’t want a funny person playing that role,” Feig explained. “I wanted somebody who had that action credibility.” Still, Feig didn’t want to see the Ford character slipping on banana peels, as Statham put it. “I didn’t want him to be a buffoon. He’s a good spy who’s so thrown off his game by the fact that somebody he considers an inferior is out over him that it just drives him crazy. And he starts making terrible decisions.”

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Rose Byrne

The last time Feig worked with Byrne, she was the prim-proper maid-of-honor in Bridesmaids. So, yes, her diabolical, foul-mouthed arms dealer Rayna Boyanov is drastic departure. Feig says the part was originally written to be “an acerbic 19-year-old rich girl,” but he retrofitted it for Byrne. The character really became fleshed out during read-throughs, when Byrne switched from an Eastern European accent (her heritage is Bulgarian) to a cold British one, and started saying really mean things to McCarthy. “But it was in a way that she thought she was being charming, and it just made it really funny to us,” Feig said. “This villain who just says whatever she wants to say, and swears all over the place.”

Watch Paul Feig talk about why he loves espionage movies:

Jude Law

No character in Spy comes off as too suave, not even Bradley Fine, the Bond-like superstar agent who Susan Cooper assists on dangerous missions. He’s played by Law, the Oscar-nominated actor typically associated with more dramatic fare. “This is totally [something new for him], Feig said. “He’s willing to take a few lumps. And get knocked around by Statham.”

Bobby Cannavale

Byrne’s real-life love interest Cannavale has enjoyed some screen notoriety, most notably as Boardwalk Empire antagonist Gyp Rosetti, so playing supervillain Sergio De Luca wasn’t a huge stretch. But Cannavale’s movie characters tend to be the good guys, if not total sweethearts. “I’m a huge Bobby Cannavale fan,” Feig said. “I’ve been desperate to work with him forever, since Win Win… When this popped up and he was interested in doing it, and he and Rose are a couple anyway, I was like, 'Oh my god, they can come out. They can have an amazing vacation in Budapest [where they filmed], and I can have the amazing Bobby Cannavale in my movie.”

Spy is now in theaters.

Watch McCarthy and Statham answer 20 awkward questions: