He’s obnoxious and small-minded—a moron, essentially. But there’s still something likable about Lawrence, the hopelessly blind optimist played by Ben Cotton in the Vancouver-shot and widely acclaimed comedy Lawrence & Holloman, opening Friday (July 18). There’s his endlessly stupid homophobia, for one thing.

“It’s ridiculous,” says Cotton, talking to the Georgia Straight at a Broadway coffee shop. “But I think it’s so hard not to like a guy when he’s so positive. It’s weird. I’ve known people like that in my life. Ultimately, it comes down to: Lawrence means well; he’s just not smart. He’s ignorant. He just says the most inappropriate and nasty things. But in the world he lives in, he just thinks, ‘Hey, that’s what we do! Where’s your sense of humour!’ He doesn’t get it at all.”

Lawrence is proudly barking into a Bluetooth about his second consecutive salesman-of-the-month award when he is first encountered by the suicidally depressed Holloman (Daniel Arnold). He begins to mentor his coworker in the power of positive thinking, not to mention the art of buffoonish self-regard, after Holloman follows him into a bar. So far, so funny. But things take an unexpectedly dark turn when Lawrence’s perfect life is rocked by a series of increasingly bizarre and violent mishaps and his relentlessly sunny outlook is really put to the test.

Writer-director Matthew Kowalchuk lies back and lets his actors do most of the work in the festival hit (which was adapted by the director and actor Arnold from Morris Panych’s 2009 play), giving them the space to make a beautifully judged comic two-hander out of the piece. Arnold’s nerdy Holloman is all slow-burning resentment and exasperation. Cotton’s Lawrence—short of his eyes shooting out of his head on stalks—is more like a Tex Avery creation come to life.

“There are a couple of moments where I watch and I go, ‘Wow,’ ” he says, recalling some of his more uninhibited on-screen moments. “The eye drops, the bee sting, even the scene with the money in the fridge, it’s so big and so frantic and cartoonish.”

The actor credits a childhood spent watching John Ritter and Don Knotts ham it up on Three’s Company for the comic sensibility. He also gives props to a past master of perfectly calibrated on-screen mania: “Gene Wilder,” he says. “Talk about somebody who’s so specific, and so broad, and so contained at the same time. It’s thrilling.”

“Thrilling” is how you might reasonably describe the chemistry between Cotton and Arnold, which Kowalchuk captures with the kind of musical feel that could have been channelled from Harold and Maude director Hal Ashby in one of his goofier moods. Cotton is touchingly modest about his own contribution to this malevolently comic triumph. “The script was so well put together that you could read and feel it. It was right there on the page, the way the rhythm needed to be,” he says.

But it took a man with true access to his inner eight-year-old to really make it sing very, very loudly.