But courage is not the only thing that makes him one of the greats, and his characters memorable: No matter how stupid or how funny or even cliche on the page, there is always a beating heart under the stupidity, a compassion that shines. Yes, even as Cookie Fleck, with all her ex-boyfriends, on “Best in Show.”

Kevin Nealon simply put: “He changed how many understood comedy and humanity.”

Because of that innate understanding of his craft, unwillingness to settle for nostalgia and unique ability to reinvent himself with each project, his characters affect many generations of fans of film, television and comedy. Before her death at age 71, she was still breaking new ground as ousted studio executive Patty Leigh in “The Studio.” And she does it all with grace and humility, a diva only when the role and costume demand it.

As fellow Canadian Sarah Polley, his partner in “The Studio,” wrote in Instagram Friday: “He’s the nicest and classiest. How is he also the funniest person in the world?”

Just eight years younger than the other comedy trailblazer Gilda Radnerthat he studied in “The Second City” in Toronto, O’Hara was not an obvious candidate for stardom as the second youngest of seven in a decidedly non-showbiz, Catholic family. But he loved comedy, was obsessed with “Monty Python” in high school and even tried to meet them at the airport one time after hearing they were flying.

His first job was not on stage, however, but as a server where he took everything he could. Although he was rejected after his first audition, he was undeterred; He joined the company in 1974. By 1976 he had become an integral part of the television cast of “SCTV,” where he created original characters and impersonated well-known personalities of the time, including Meryl Streepwho was later his acting partner.

“My crutch, in improv, when in doubt, is to play crazy,” O’Hara told The New Yorker in 2019. “You don’t have to excuse anything that comes out of your mouth. It doesn’t have to make sense.”

By the time the show ended in 1984, he was itching for something more, something deeper and began reading scripts for films. Others have equated his pickiness (including being pulled from “Saturday Night Live”) with a kind of lack of ambition. For him, it’s about waiting for the right thing. Although his film debut was not very good (in the poorly reviewed Canadian thriller “Double Negative” with “SCTV” peers such as John Candy and Eugene Levy) he soon found his footing working with the likes of Martin Scorsese in “After Hours” and Mike Nichols in “Heartburn,” where he will play Streepway’s gossipy friend.

“You have to try to make this person a real person,” he said in a CNN interview in 1986. “When I first read it, I thought this woman is doing nothing but gossip.

It was a motivation that served him well during his rise to Hollywood in the late 1980s and early 1990s. You can watch “Home Alone” for the hijinks, but O’Hara makes it emotional and believable as the mother tries to get her son back. There was humor, yes (remember the fake Rolex?) but then, a beat later, there were tears. Even Delia Deetz is talkative, giving her husband a lecherous glare at his tone-deaf suggestion that he can now make a decent meal in his new suburban prison.

She loves period garb as Wyatt Earp’s sister-in-law, is crazy as Colin Hanks’ depressed, overworked mother in “Orange County,” and is crazy as Marty Funkhouser’s brother Bam Bam in “Take Your Enthusiasm.”

From his point of view, there is nothing as big as “Schitt’s Creek,” an unlikely cultural phenomenon that has everyone suddenly pronouncing the baby “bébé” (and it’s not because of the sudden surge of the French language on Duolingo). Few actors can create their own speech and cadence as O’Hara does with Moira Rose.

That unmistakable and unmistakable accent, he told Rolling Stone in 2020, was “in defense of creativity.” She was inspired by the women she met over the years who, out of insecurity and pride, created new personas out of whole cloth. As far as the view goes, the socialite Daphne Guinness is the beginning.

“I think that Canadians not only have a sense of humor about others but about themselves, which I think is the healthiest and best kind of humor to have,” he said in the same interview with Rolling Stone. “There’s an edge to it but there’s compassion and love.”

Just think of Levy’s Mitch and O’Hara’s Mickey in Christopher Guest’s “A Mighty Wind” singing that mock folk song “A Kiss at the End of the Rainbow” with its saccharine sweet lines. This is ridiculous. Funny. And you might just cry a little.