Adrian Martinez wasn’t the first choice to play “Fatass Farhad”, the vulgar sidekick to Will Smith and Margot Robbie’s lovebird con artists in Focus (opening Friday [February 27]). The role was, apparently, offered to Artie Lange, formerly Howard Stern’s vulgar sidekick, but Lange took offence at the unflattering moniker and mocked the opportunity on his sports talk show.

On the phone from Toronto, Martinez says he used his experience in theatre to craft a back story and a more interesting take on Farhad than his nickname suggested. “I was able to see past the superficial aspect of the fat joke and just see that this guy is an important part of the script,” Martinez explains. “He’s not just the comedic relief. He’s the one guy that Nicky, played by Will Smith, trusts. And that, to me, superseded any other consideration.” (Thankfully, that consideration only came up around the script. Farhad isn’t called by his nickname in the film.)

Martinez also has a thoughtful explanation as to why Farhad is so crude with Robbie’s character and why she laughs instead of smacking him. “I think Farhad was testing her when he says those things. He just wants to know, like, what exactly is going to throw this person,” he suggests. “Because, remember, he’s a con man and he wants to know who he’s playing with. And I think it’s all in good fun and it’s the kind of dialogue where she’s so secure in herself that she’s not going to let this clown upset her in any way.”

Some of this dialogue was improvised, but Martinez won’t say which jokes were his. He’s definitely got a quick wit: when asked if he’s ever shot a film in Vancouver, he teases, “No, but I accept your offer.”

The veteran character actor doesn’t need to joke about taking any old offer. He’s been in some cool stuff over the years, from procedurals like NYPD Blue and all the Law & Order series (“One time I played a mentally disabled guy who was confused for the perp. And what was interesting was I didn’t have to audition. So someone somewhere said, ‘We need a guy who’s not well. Let’s call Adrian.’ ”) to more recent oddball fare like Louie and American Hustle.

His next cool film is Sisters, but he won’t be the comic relief again. “I play a hard-edged cop who gives Tina Fey and Amy Poehler a hard time,” he says. “I’m kind of like the straight man and they’re the clowns. You gotta know your place when you do a movie.”

Not surprisingly, he sounds a bit awestruck by Fey and Poehler. “I tell ya, those ladies, I think we’re going to look back and say, wow, we were in the midst of a genius comedic pair. I look at how they just nailed the Golden Globes. I think we’re talking about real, real genius when you talk about those two.”