In 1982, Robert DeNiro starred in Martin Scorcese’s “The King Of Comedy,” the tale of a man named Rupert Pupkin, who is obsessed with late-night talk-show host Jerry Langford (Jerry Lewis). Desperate to get on Jerry’s show, Rupert finally kidnaps the star with the help of another stalker named Masha (Sandra Bernhard, in the only good thing she’s ever done). The ransom Rupert demands in exchange for Jerry’s release is to be able to appear on the late-night show to do a comic monologue.

When Pupkin gets the opportunity, the material he’s written isn’t that funny and though he’s clearly rehearsed for quite a while, his delivery is stilted. Still, the audience laughs along and Rupert becomes a star.

Now, 35 years later, we get “The Comedian,” which should have been called “Rupert Pupkin Gets Old.”

This time, Robert DeNiro is Jackie Burke, a veteran comedian whose career is on the skids. He had a hit TV show 30 years ago that he’s still recognized for, but he’s not really in demand. The first gig we see him do is at a comedy club on Long Island with two other TV has-beens, Brett Butler and Jimmie Walker. During Jackie’s set, he goes after a heckler who’s egging him on for a YouTube video series. Jackie decks the guy, who files charges. Jackie goes to jail for a month, then has to do community service at a place that dishes out food to the homeless.

That’s where he meets Harmony (Leslie Mann) and, despite the age difference (he’s 73, she’s 44), they fall for each other, of course. Harvey Keitel shows up as Harmony’s father, who isn’t happy that his daughter won’t move down to Florida and work in his old-age homes. Mann’s character is ridiculous — a woman in her forties who dates a man three decades older while being told what to do with her life by her rich, obnoxious father.

Meanwhile, Jackie has to go to his brother (Danny DeVito), who runs a deli, to borrow money. It’s at this point that I should mention that both Jackie and his brother are supposed to be Jewish. So, who do you cast to play cranky old Jews? Why, two guys named DeNiro and DeVito, of course!

As badly written as Mann’s character is, Patti Lupone suffers more as DeVito’s wife — all she gets to do is nag and complain. Later, Jackie meets his agent (Edie Falco) at the Friar’s Club, where’s he forced to suck up to Dick D’Angelo (Charles Grodin), a comic who’s stolen bits from Jackie, in order to get on a TV special honoring May Conner (Cloris Leachman) for her lifetime in comedy.

The movie is full of scenes like that and two others that were pulled from the bottom of some humorless well. One takes place when Jackie gets up at his niece’s lesbian wedding and insults all the relatives and other attendees. The other one has Jackie leading a roomful of seniors in a song about going to the bathroom.

None of it works, at least partly because it’s so hard to make movies about stand ups with actors who aren’t comedians. Tom Hanks and Sally Field couldn’t do it in “Punchline.” Seth Rogen and Adam Sandler (who used to be a standup) couldn’t do it in “Funny People.” Even Billy Crystal couldn’t make a hit out of “Mr. Saturday Night,” although he was much better at mining the same bitter-old-comic turf for laughs. As for DeNiro, his comic delivery and timing haven’t improved since his days as Rupert Pupkin.

If you want to see a terrific movie about what it’s like to be a standup, see Jerry Seinfeld’s 2002 documentary “Comedian,” in which he starts his post-sitcom life by throwing out all of his old material and going on the road to develop an entirely new act. You’ll see the hard work it takes to come up with ideas, turn them into jokes with just the right pacing and wording, and create the finished product that is a real comedy routine.

Don’t confuse it with “The Comedian” which, despite actual comedians like Jeffrey Ross and Jim Norton helping out on the script, isn’t very funny at all. Instead of gathering together a cast of non-comics, perhaps director Taylor Hackford — who made “Ray,” “An Officer And A Gentleman,” and “Hail Hail Rock And Roll” — should have just filmed some of the comics who make cameo appearances in “The Comedian,” like Hannibal Buress, Gilbert Gottfried, Jessica Kirson, and Nick Di Paolo. At least they know what to say and do behind the microphone, unlike DeNiro.

 I give “The Comedian” a 2 out of 10.