Saturday Night

As fan service for old-school “Saturday Night Live” aficionados, Saturday Night is steeped in scrappy nostalgic appeal while falling short on genuine insight.

This playful and immersive backstage saga from director Jason Reitman (Ghostbusters: Afterlife) pays an affectionate tribute to the 50-year-old show’s groundbreaking nature and enduring legacy by returning to its humble roots.

The madcap result often feels exaggerated to the extent that you wonder how much of it is true. Yet embellishments aren’t necessarily the issue. For all the ticking-clock mayhem and breakneck pacing, the film struggles to build underlying tension as it funnels toward an inevitable climax.

It unfolds almost in real time at NBC headquarters on the night of Oct. 11, 1975, in the buzzing 90 minutes leading up to the debut of the ribald new sketch comedy show from producer Lorne Michaels (Gabriel LaBelle).

Among the ragtag troupe of quirky performers, Chevy Chase (Cory Michael Smith) is hurling insults left and right, especially toward John Belushi (Matt Wood), who still hasn’t signed his contract. Dan Aykroyd (Dylan O’Brien) is feeling insecure, Gilda Radner (Ella Hunt) is spaced out, and Garrett Morris (Lamorne Morris) is questioning his role.

As showtime approaches, it’s an anarchic whirlwind of manic energy, anxiety, anticipation, and self-doubt, where each second brings a new soul-crushing crisis, with the plucky Michaels and Dick Ebersol (Cooper Hoffman) as the ringmasters.

That doesn’t even count snarky intrusions from Johnny Carson and Milton Berle (J.K. Simmons), or objections from censors and network executives. “Perhaps you kids aren’t quite ready for prime time,” barks a programming boss (Willem Dafoe).

The crew is revolting, the writers are drunk, and the studio equipment is faulty. The only saving grace is low expectations.

Reitman captures the chaos with swirling cameras including some bravura tracking shots, as well as a rhythmic, percussion-heavy Jon Batiste score. The frenetic pace has its drawbacks, however, when it comes to developing the real-life characters or replicating their comic talents beyond mere snippets.

Some of the jokes hold up better than others. Many of the gags are silly and sophomoric, and politically incorrect by today’s pearl-clutching standards — which often makes them funnier.

Regardless of your affinity for “Saturday Night Live” or sketch comedy in general, you can still appreciate the groundbreaking nature of their achievement and applaud them for somehow making it work. You wish Saturday Night had done the same.

Rated R, 108 minutes.