Even the superest superfan of the legendary US TV comedy show Saturday Night Live is going to struggle with the unbearable self-indulgence and self-adoration of this exhausting film from director and co-writer Jason Reitman.

It’s a frantically dull dramedy about the supposedly adorable chaos that attended the show’s first ever live broadcast in 1975, with all the iconic players including Chevy Chase (Cory Michael Smith), Dan Aykroyd (Dylan O’Brien), John Belushi (Matt Wood), Gilda Radner (Ella Hunt), and Garrett Morris (Lamorne Morris). For some obscure and not obviously funny reason Nicholas Braun plays both Jim Henson (of Muppets fame) and Andy Kaufman, and Gabriel LaBelle plays the show’s presiding producer-genius Lorne Michaels, who announces that his experimental comedy wackfest is “the first television show by and for the generation who grew up watching television”.

The film is filled with endless swooping travelling shots as everyone rushes around corridors in wacky costumes, arguing about scripts, panicking about overruns, accidentally smoking weed (yikes!) and, underneath it all, Michaels suspects that the station chiefs have secretly set his show up to fail as part of their contract negotiations with Johnny Carson, to persuade the great man to keep working weekends.

JK Simmons has a cameo as obnoxious oldster comic Milton Berle, boasting about and indeed displaying his fabled manhood and Willem Dafoe is NBC exec David Tebet, who is unsure whether these crazy kids are any good. Tina Fey’s TV masterpiece 30 Rock (based on her writing work on SNL, with Alec Baldwin as the Lorne-Michaels-esque boss Jack Donaghy) has frankly covered all this kind of thing much more entertainingly and the same could be said of Richard Benjamin’s 1982 film My Favorite Year, about SNL forerunner Your Show of Shows. There’s an odd, disconcerting tone of solemnity to this slice of cultural history.

• Saturday Night is in UK and Irish cinemas from 31 January.