Jesse Plemons is that fleshy redhead who shows up in a movie and makes you go, “Oh, it’s that GUY.” He was the scary square cop from “Game Night,” the square too-young lawyer in “The Post,” a green cavalry trooper in “Hostiles,” the clueless sheriff in “American Made.”

See a pattern here?

But “Saturday Night Live” writer Chris Kelly looked outside the box Hollywood has painted Plemons in and builds his dramedy “Other People,” around him. And if Plemons isn’t up to carrying the “comedy” part of this, he’s quite sharp in dramatic scenes as he plays a struggling New York comedy writer (ahem) who comes home to Sacramento to help care for his dying mother (Molly Shannon).

David never imagined his homecoming would be like this. He left college to local newspaper acclaim as a writer headed to New York to seek fame and fortune. Updates on his getting a shot at this series pilot, or that one, filled the family scrapbook.

Seven years in New York, and his latest pilot has been dismissed. A relative mentions looking for him on “Saturday Night Live.” Not his employer. Besides, he’s a writer, not a performer.

“Only a matter of time before we see you on there.” Encouraging. He just needs some material.

“I’ve got material RIGHT here,” his grandpa (the great Paul Dooley) cracks.

Topping all his personal disappointment? Mom’s been diagnosed with leiomyosarcoma.  As the movie opens with a tearful deathbed scene, we know how that’s going to turn out.

What “Other People” is about is how this family gets to that point, a year of treatment, despair, collapse and coming to terms with how these people relate to each other, but mainly how David struggles to look outside of himself and overcome both the external forces beating him down, but his own self-absorption and limitations.

Dad (Bradley Whitford of “Get Out”) never got over David coming out. Their time with his mother is an uneasy truce.

David’s sisters (Maud Apatow and Madison Beaty) are hurting, too. But he’s too into his own head to see it.

And then there’s his relationship with Sacramento, which, as “Lady Bird” and other films have taught us, is the squarest corner of California.

Shannon is the heart of “Other People,” bucking up and dissolving into tears, riven by grief and regret on bad days, stiffening her upper lip on good ones. One moment, she’s apologizing “for all the bad things I said when you came out,” another, she’s getting a mom massage, morbidly curious if her son can “see it,” “it” being the cancer that’s all inside her with little physical manifestation on her exterior.

Whitford’s a good actor, but Kelly does nothing to expand, justify or make us believe his character’s homophobia. He’s constantly encouraging his son to hit the gym, take some “boxing classes,” as if he believes it. Nobody, including Whitford, does.

The film’s stand-out funny moments are provided by the grandparents (Dooley and Jude Squibb), and by John Early, playing Gabe, a gay friend who also moved away and is home on occasion, and especially by J.J. Totah, playing Justin, Gabe’s flaming — only word for it — much younger adopted brother.

Justin is the gayest middle schooler the movies have ever seen, embracing the stereotypes long before he embraces his sexuality — obsessive about his room decor, cross-dressing and carrying himself with a confidence that David or Gabe never would have when they were his age. He’s so hilarious he stops the movie, which isn’t exactly sprinting along.

One reason to include those Justin moments — making a perhaps stereotypical point about gay narcissism?

Plemons has a few almost-comic moments, a drunk scene, and a couple of big speeches, none of which lift “Other People” out of the dragging, month-by-month (intertitles tell us which month it is) march toward the inevitable.

What is Kelly saying here, that David has to get past the “It’s all about me” thing? That’s a serious hole in the film — sweet speeches about a dying woman telling her son how much she loves birch trees, and how he (Gabe) will think of her every time he sees one — mixed with blase OKCupid hook-ups, interludes of watching gay exibitionism online, Justin, mixed with Mom failing, Dad trying to talk David through a Living Will and the like.

It’s worthwhile enough to justify the film being made, but just barely. Kelly’s made a self-absorbed dramedy about a character not-quite-making-his-mom’s-cancer-about him, but close, one that never comes to grips with more than random observations about this life, this world and how it isn’t really changed by this character’s mother’s death.

MPAA Rating: unrated, sexual situations, profanity, marijuana use

Cast: Jesse Plemons, Molly Shannon, Bradley Whitford, Maud Apatow, June Squibb, Paul Dooley

Credits: Written and directed by Chris Kelly. A Vertical/Netflix release.

Running time: 1:36