Grant Judd Apatow this.

Pete Davidson, perhaps the quintessence of “comic as acquired taste” as a member of the cast of “Saturday Night Live,” grows on you during “The King of Staten Island.” By the third act of this highly fictionalized riff on Davidson’s life story, the son of a New York firefighter killed on 9/11, you understand something of what it’s like to grow up carrying the weight of a martyred hero on your shoulders.

Whether that’s enough to alter one’s overall impression of “King” comes down to your tolerance of Apatow’s inability to edit, to kill his (limp) “little darlings,” scenes that don’t add laughs, drive the story or greatly deepen our understanding of the hero’s journey. And Davidson’s inability to carry a comic or serio-comic feature film, proven in the slightly-funnier if less consequential “Big Time Adolescence,” figures in the equation, too.

We’re some 100 minutes into the picture before the grating, gauche Davidson — and his character, Scott Carlin — achieves “Well, we should cut the kid a break” status. Apatow pictures always run long, but here the thin laughs make us reach “All RIGHT already” far too soon.

Scott is well into his 20s, unemployed and almost unemployable, still living with his widowed Mom (Marisa Tomei) and sister (Maude Apatow), who is about to graduate and head off to college and frets over her morose big brother.

“Be nice to MOM!”

Scott has a cannabis crew (Moises Arias, Lou Wilson, Ricky Velez), here primarily to illustrate Scott’s aimlessness, and serve as punch lines for his insults — “Look, ‘Fat Kanye,’ shut your pie hole!” — and as sounding board for Scott’s BIG IDEA.

“Ruby TatTOOSdays!” Get a tattoo while you eat?

First, aspiring artist Scott has to develop tattoo skills. He practices on his friends. And then he’ll need backers but well, it’s not likely he’ll ever clear that first hurdle.

He has a sometime sex partner/might-be “girlfriend” (Bel Powley), but it’s hard to have a relationship when you’re depressed, with Crohn’s Disease and ADD so severe that he has almost zero impulse control.

That’s how he decides to tattoo a random child he and his pals run into one afternoon. That’s how the kid’s raging dad, Ray (Bill Burr, who steals the movie) meets his mother — chewing her out because “You didn’t even RAISE him.”

But when Ray finds out who the kid’s father was, he softens. When he cools off, he realizes this is a pretty widow he’s bawling out. Dating begins, and maladjusted Scott has one more thing he cannot cope with on his “Things to not get over” plate. Ray is also a firefighter.

No, the movie doesn’t take necessarily take the predictable turns you expect from here on out. More credit to Apatow. But when you’re throwing in scenes from a part-time restaurant job for Scott (which exist to set up a single funny bit), firefighters bonding moments, the on-and-off “girlfriend” thing, Mom’s pursuit of happiness and Scott’s desire for destruction — his and others’ — a little of what your throw against the wall just might stick.

Burr does. The talented Powley almost does. Tomei doesn’t embarrass herself.

The jokes are of the miss-miss-or-hit variety, like explaining the symptoms of Crohn’s Disease in scatological and gross detail.

“Hey, I’m just trying to spread awareness.”

Scott’s self-deprecation at every point — “I’m just stupid…I’m just an a–hole.” — doesn’t make him endearing, just self-aware.

But they’d all have to turn in their union cards if they couldn’t get some sentimental, lump-in-the-throat moments over a dead 9/11 firefighter. A streamlined script that got rid of a some of the random and zeroed in on that (Steve Buscemi plays a fellow firefighter) would have helped.

As it is, the best thing to happen to “King of Staten Island” was the high-profile digital release COVID 19 gave it. Davidson’s fans will find it, and Apatow devotees. But let’s just say Davidson’s renewed threats to quit SNL (“Nobody there likes me.”) stopped at around the time he saw a final version of his latest movie star vehicle.

MPAA Rating: R for language and drug use throughout, sexual content and some violence/bloody images

Cast: Pete Davidson, Marisa Tomei, Bel Powley, Bill Burr, Steve Buscemi.

Credits: Directed by Judd Apatow, script by Judd Apatow, Pete Davidson and Dave Sirus. A Universal release.

Running time: 2:16