Star Rachel Sennott posted a TikTok this week giving a glimpse of several of the actors dressed up for their roles. There's Ella Hunt as original SNL cast member Gilda Radner, Sennott herself as Rosie Shuster (writer and ex-wife of show creator Lorne Michaels), Kim Matula as another OG cast member, Jane Curtin — and then there's O'Brien.

"I hear we're very similar, in a way that I never knew," O'Brien also tells PEOPLE of himself and Aykroyd, whom he plays in the film

Depicting the first ever taping of 'Saturday Night Live', Dylan O'Brien appears in the film's ensemble as OG cast member Dan Aykroyd.