Stop me if you’ve heard this one before: There are some standup comedians out there (many of them irascible men) who dare to talk about their sex lives, their anger issues, and their various inadequacies on stage—often while using a lot of bad language. Further, the friendly sitcom stars of our youth, whom we know best as sanitized parent figures accompanied by a hearty laugh track, actually tend to be flawed individuals in real life. If all of this is news to you, then you may find Taylor Hackford’s film The Comedian to be a revolutionary piece of art.

Otherwise, you’ll see it as a useless throwback—a fetid, overlong drama laden with bizarre subplots and an inexplicably star-studded supporting cast, built around the dated idea that standup comedians can, indeed, be jerks. The Comedian has all kinds of pedigree: a grumbly Robert De Niro in the title role, an Oscar-nominated director (for Ray, Hackford’s last big hit), and an ensemble that includes Edie Falco, Harvey Keitel, Patti LuPone, Charles Grodin, and Danny DeVito. But this film serves as a good reminder that in moviemaking, pedigree can only take you so far.

The comedian in question is Jackie Burke (De Niro), once the star of a ’70s (possibly ’80s) sitcom where he played a wise-guy cop with a crazy family, who’s now a semi washed-up standup who makes his money at nostalgia comedy nights or signing autographs for increasingly older fans. He’s a toxic mix of bitterness, loneliness, and relative poverty, managed by a straight-faced comedy booker (Falco) and resented by his restaurateur brother (DeVito) and sister-in-law (LuPone). The insult comedian Jeff Ross has a writing credit on the film and supposedly provided much of its onstage material—rancorous and foul-mouthed, but lacking any hint of irony or an artistic sensibility. Like Louis C.K., but without the self-awareness.

De Niro is coasting, as he so often has in recent years, but he’s still not bad. Being a standup requires a particular presence and a strangely confident approach to being pathetic; De Niro largely nails that, taking the stage with sullen ease, and barking penis jokes as if he’s done it for 40 years. His material isn’t special, but it’s authentic enough, the kind of thing one might expect from a night at the Comedy Cellar in Manhattan’s Greenwich Village, where a good chunk of the film takes place (including, alongside De Niro, snippets from several actual pro comedians).

However, the life of an over-the-hill club comedian is hardly the stuff of heady cinema. It’s particularly well-worn territory given the recent efforts of TV stars like C.K. and of the director/producer Judd Apatow, the auteur of the “self-loathing bastard” subgenre (whose Funny People was a more piercing, if similarly bloated, exploration of the mind of a faded star). Perhaps you’d expect one other parallel plot for The Comedian, to run alongside Jackie’s efforts on the standup circuit. Instead, The Comedian’s saggy script (which has four credited writers, including Ross) tosses in every twist of fate imaginable.

Early on, Jackie gets in an altercation with a heckler at a standup set and punches him; given the chance to apologize by a judge, he refuses and goes to prison. Stuck doing community service, he meets Harmony (Leslie Mann), a fellow self-loathing miscreant that he immediately falls for, despite their 29-year age difference. Unfortunately, that necessitates dealing with her father Mac (Keitel), some sort of retired mobster with a serious attitude problem. Burke also keeps getting on the wrong side of his brother, with a whole extended set piece taking place at his niece’s wedding. There’s also a bunch of funny business at the Friar’s Club, presided over by an imperious hack (Grodin); a segment in which Jackie hosts a Fear Factor-esque game show straight out of 2002; and a random trip to Florida, where he improvises a scatological version of “Makin’ Whoopee” to a crowd of scandalized geriatrics.

On and on it goes, with each new plot element more nonsensical and disconnected than the last. It’s almost like The Comedian is trying to distract from the inherent ridiculousness of its central romantic pairing by throwing celebrity cameos and grumpy mobsters at the audience. Eventually, it resorts to a late-stage twist so hackneyed and groan-worthy I almost called it quits right there (fear not—I stuck it out through the ending, which includes a surprise time-jump).

One could call The Comedian a waste of De Niro’s skill, but he’s also the man who made Dirty Grandpa last year. He’s not trying very hard here, but even so, he’s a fairly magnetic presence—though that certainly doesn’t justify the cost of admission. Mann, on the other hand, is a genuine talent so often thrust into these sorts of roles: women defined only as having a chip on their shoulders, in need of some half-hearted attempt at taming. The Comedian does her this usual disservice, despite her best efforts, and it’s similarly unappreciative of its supporting actors. If you’ve long dreamed of seeing De Niro croon fart jokes into a microphone, then The Comedian belongs on your bucket list. Otherwise, just wait for his next mediocre comedy—no doubt another one is right around the corner.