Rachel Sennott didn’t get into the premier sketch comedy group during her tenure at NYU. Now she’s playing one of the architects of the world’s most famous sketch comedy show in Jason Reitman’s Saturday Night. Co-written by the latter and Gil Kenan, the biographical comedy-drama chronicles the messy 90-minute period before the first episode of Saturday Night Live on Oct. 11, 1975. Sennott portrays writer Rosie Shuster, who’s also the first wife of SNL creator Lorne Michaels (Gabriel Labelle). And much like their ambitious attempt to shake up NBC’s Saturday night programming, their marriage, as depicted in the film, is in a similarly fragile, yet oddly collaborative, state.

In contrast with a lot of her castmates, Sennott didn’t have a great deal of existing material to reference during prep, but she did have the ultimate resource one phone call away.

“I spoke to Rosie, which was amazing.