Jason Reitman recalls the 'almost impossible' task of finding the right actor to play Dan Aykroyd in Saturday Night

Jason Reitman is fully aware of how big of a risk it was to make his new movie Saturday Night — about the frantic 90 minutes leading up to the first-ever episode of Saturday Night Live in 1975 — mostly due to one crucial aspect...the one many consider the most important part of making any movie.

"Casting this was the scariest part of the process," the twice Oscar-nominated director for Juno and Up in the Air (plus another two for writing and producing the latter), says on the latest episode of The Awardist podcast. "The moment I would tell people we're making a movie about the opening night of Saturday Night Live, people would go, 'Oh, great idea. How the hell are you going to cast this thing?' And I was really intimidated.'"

He credits casting director John Papsidera for having a "particular gift for finding talent." (The two first worked together on 2014's Men, Women & Children, "where we put Timothée Chalamet into his first movie and worked with Ansel Elgort and Kaitlyn Dever before people really knew who they were," Reitman recalls.) Reitman, who co-wrote Saturday Night with Gil Kenan, says finding his Lorne Michaels was easy: "I remember seeing [Gabriel LaBelle] for the first time [and thinking], 'All right, this guy's perfect.'" It was a "no-brainer" that Lamorne Morris should play Garrett Morris.

Among the many others: Cory Michael Smith as Chevy Chase; Ella Hunt as Gilda Radner; Kim Matula as Jane Curtin; Matt Wood as John Belushi; and Emily Fairn as Laraine Newman. But one cast member of that inaugural season proved especially difficult.

"[Dan] Aykroyd was almost impossible," Reitman admits. "Dylan [O'Brien] came very late in the process, and it was, thank God. I mean, that was a big moment. He was the final of the seven, and it was like, 'All right, we have our cast.'"

"Dylan is so good in the movie. He brings something so subtle and layered," interjects LaBelle, sitting next to Reitman during the interview conducted two days before the film's premiere last month at the Toronto International Film Festival. "I remember hearing his voice for the first time in the table read and just going, like, 'Motherf---er.'"

For his part, LaBelle, who rose to fame playing a version of Steven Spielberg in the director's semi-autobiographical film The Fabelmans, took on another famous creative and storyteller. A Jewish Canadian like himself, LaBelle says he connected with Michaels, a "true powerhouse" and "an outsider looking at the world [from] a unique perspective."

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But he admits one of the roles was more daunting than the other.

"Playing Steven was viscerally, physically, emotionally, and spiritually a lot more intimidating because I'd been acting since I was 11, being on sets and whatnot, but that was the biggest and most important-feeling job I'd had in my life. And he's right there — he's right there, he's watching you. You don't want to ruin his life," LaBelle recalls of his fears working on that 2022 movie. "I hadn't been validated yet as an artist or an adult. I just graduated and spent a year in COVID, so I was very much like, 'What am I getting myself into?' But then I had worked on a number of things post[-Fabelmans] before SNL, and turns out people liked my work in The Fabelmans and I didn't have to jump off a bridge. And I'd spent more time growing as an actor and as an artist....I showed up to this movie, I think, more relaxed than I have any other job in my life."

Listen to Reitman and LaBelle's full interview on The Awardist podcast, below.

Saturday Night is in theaters now.