Saturday Night (Netflix) is presented as the 90 minutes leading up to the first episode of Saturday Night Live. I think it is mostly based on fact, although I do not think most of the events in the movie actually happened in the 90 minutes before the show. Some of it was in the days and weeks leading up to it, and a few events happened weeks and even years after the first episode of SNL. The movie makes Lorne Michaels look like a hero, but presents a complicated picture of the rest of the cast, which is interesting. Belushi and Chase are arrogant, and Aykroyd is weird and a little creepy. The three main female actresses from that first season, Curtain, Radner and Newman, seem just happy to be on the show in the movie, which was not what I was expecting. I wanted more Curtin in the movie, who, in real life, was a normal life person with model looks that always seemed out of place in that SNL environment, and more of her perspective would have been interesting. The movie acknowledges that the show did not know what to do with a very talented Garrett Morris. Michael O'Donaghue was nuts in real life, and comes off nuts in the movie. Others at NBC at the time, like Milton Berle and Johnny Carson, are skewered, especially Berle, and by all accounts, he was a terrible human being in real life.
I think playing a real person that everyone already knows is really hard, and the actors that played Chase, Aykroyd and Belushi did a great job. Nick Braun was fantastic playing both Jim Henson and Andy Kaufman. JK Simmons was really repugnant as Berle while still making it credible that so many of that generation really liked Berle.
If you like this movie, I would recommend Netflix's A Futile and Stupid Gesture, which is about Doug Kenney and the founding of National Lampoon, kind of an origin story for SNL. I think of these as really important movies about a seismic change in our culture that was reflected in comedy of the 1970's. Comedy, by its nature, does not age well, but National Lampoon and SNL completely changed the arc of comedy from the Johnny Carson's sight gags and silly one-liners and puns, and Milton Berle's and Henny Youngman's reductive misogyny of wife jokes and dressing up like women to mock women, in addition to the barely concealed racism of so many comics of that era. National Lampoon and SNL blew all of that apart. Movies changed, TV comedy changed, and our culture changed. I think comedy reflects the culture, but the seismic shifts in our society in the late 70's were not being captured by traditional comics prior to National Lampoon and SNL.