George Clooney fans, be forewarned: If you’re hoping to catch a breezy, smart comedy-drama by watching his new Netflix film “Jay Kelly,” know that it begins with a Sylvia Plath quote and goes on to treat its story of an aging movie star sentimentally.

Despite what seems, from its preview, like a playfully satirical view of Hollywood and stardom, as well as a fun romp through Paris and Italy, the actual picture contains very few jokes, witty observations, flights of fancy, glamor, or insight. Not even Adam Sandler, who portrays Mr. Clooney’s titular character’s manager, Ron, can inject much mirth into the proceedings, though he’s one of the best things about the movie.

Mr. Clooney has more than proven he can do dramedy, with prime examples including “Up In The Air” and “The Descendants.” Unfortunately, his latest foray into the serio-comic genre leans heavily on the “serio” side, delving into the effects of narcissism as it simultaneously extols the virtues of idolization.

Director Noah Baumbach, who also knows the genre well (“While We’re Young,” etc.), does affect a vaguely absurd tone at times. Yet his flat, Fellini-lite approach whittles away the story’s bite and renders the rare whimsicality inane instead of intriguing, eventually reducing the movie to a painfully drippy ego trip taken by the character and its actor. The film purports to be a paean to the cinema but its truest dedication is to schmaltz. 

The opening scene sees Jay perform the final take of a nearly completed picture. His character is dying on a New York City street, and though the scene is filmed within a soundstage and involves a cute dog, the earnest monologue he delivers demonstrates how “Jay Kelly” will favor philosophical hokum over wry imagination.

Further scenes involve the funeral of a beloved director and jibes at Hollywood and Jay’s disconnection from the “real world,” resulting in an almost dark comedy feeling, especially when he reconnects with an old acting buddy from his younger days, Tim (Billy Crudup).

At a dive bar, Jay and Tim catch up and reminisce, though eventually a decades-old grievance of Tim’s rears up. This turn of events and an earlier moment in which the latter reads the menu as if it were his last will and testament effectively explore the mockingly dramatic, the melodramatic, and everyday acting. One wishes the rest of the film were as incisive.

Soon, a desultory plot is introduced in which Jay flies to Europe to spend time with his youngest daughter, as well as attend a tribute ceremony, and what was mildly engaging beforehand becomes trite and sappy, particularly as Jay remembers events in his life.

The film’s second act — and centerpiece — constitutes the train journey Jay takes from Paris to Tuscany. Riding in coach with the rest of the plebeians, Jay regales and is regaled by the other passengers, who look on him as if at a god.

With a scenario ripe for a comedy of manners on board, or at least a few humorous misunderstandings between Jay and his fans while in close quarters, Mr. Baumbach chooses European stereotypes and general geniality instead, turning his attention to Ron’s relationship with Jay’s publicist, Liz (a harried Laura Dern), as well as Jay’s reminiscences. Most of these are run-of-the-mill, psychologically inconsequential, and indifferently shot (e.g., Jay recollects a love that got away).

As these flashbacks start to drag the narrative, Mr. Baumbach attempts to enliven things through a bit of action involving a passenger, though this sequence proves ludicrous. Like most of the film, it’s not entertaining enough to suspend disbelief, nor is it plausibly envisioned to flirt with the absurd. 

When Jay and Ron arrive in Tuscany for the tribute, additional inanities transpire, such as when an Italian liaison explains the people and pleasures of Italy to a major movie star as if he had never been before. The presence of Stacy Keach as Jay’s imperious father picks things up a bit, but ultimately he’s as toothless as the movie. 

As the third act continues the film’s descent into strained family drama, weak humor, and banality, it nevertheless offers Mr. Sandler moments to shine as the loyal-but-questioning Ron. Issues of work/life balance, the difference between a professional family and a real one, and the entanglement of one’s efforts and emotions in another’s output are all brought up through the character and his struggles with Jay, though Ron’s quandaries come secondary. 

The director’s main concern is viewing celebrity through the distancing gazes of shallow adulation and jaded curiosity, giving Mr. Clooney not much to play, particularly when he “looks back” at his life.

Written with him in mind, the screenplay by Mr. Baumbach and actress Emily Mortimer (who also appears as Jay’s hairstylist) treats the actor like the character is treated in the film: with kid gloves, indulgence, and spasms of sarcasm. Mr. Clooney turns on the charm when he can, but the role as written is devoid of personality and thankless, even if, in the end, it does include a montage of some of his best parts. It’s a highlight reel for a film with nearly none of its own.