“The New Pope,” premiering Monday on HBO, is creator/director Paolo Sorrentino’s striking but completely unnecessary addendum to his wildly imaginative, provocative (and frankly much better) 2017 series, “The Young Pope.”

Nearly everything that worked so well the first time falls apart in the new series, which becomes a languorously long, frequently cryptic epistle on the sin of letting style conquer substance. Even so, “The New Pope” is quite something to look at and linger over. It’s 2020’s first strong contender for television’s tl;dw award (too long; didn’t watch).

Having rolled around in all nine hours of “The New Pope,” much of that time spent in a state of confoundment (and letdown, since I was a big fan of Sorrentino’s earlier effort), I wonder if timing might be the real issue here?

“The Young Pope” serendipitously premiered in the days leading up to President Trump’s inauguration, and its overall metaphor, while unintended, seemed eerily apt. Jude Law starred (and returns here) as Cardinal Lenny Belardo, the surprise choice among his fellow cardinals to be the next pontiff. Taking the name Pius XIII, he was a hard-line (and hard-bodied) pope. His address at St. Peter’s Square detonated in a way similar to Sean Spicer’s first White House news conference — a tantrum of new rules and a rejection of old-school protocol.

Sorrentino then set about with a seductive, often gorgeously surreal story that stripped a corrupted Catholicism down to an essence of love. As the elegant yet often inscrutable Pius shunned the usual duties and public persona of official popedom, he most vexed the Vatican’s longest-serving secretary of state, Cardinal Angelo Voiello (Silvio Orlando, in a magnificent performance), who did everything to thwart the young pope. That is, until he saw what others (including a nun played by Diane Keaton) had already seen. Voiello realized he was in the presence of modern holiness; a pope so in touch with God that his words and actions verged on the miraculous.

“The Young Pope” ended on a note of ascension. Pius collapsed from sudden cardiac arrest. Some viewers logically presumed he died, as the camera zoomed upward from his beatific face, away from Earth and into the cosmic heavens. Then and especially now, there’s a strong argument for leaving it there.

Yet here we are, back in lush Vatican gardens as Voiello and his cabal prepare for a new conclave to pick Pius’s successor. Pius XIII is not dead; he’s in what his doctors have pronounced a permanent coma, on life-support in a hospital bed (beneath a giant, neon red-and-white cross) in a chapel in Venice, while his faithful keep a constant prayer vigil outside. A nun sits with Pius day and night, occasionally giving his naked body a sponge bath.

Sorrentino’s artistic obsessions go to extremes in “The New Pope” — every shot is framed for maximum visual interest by a filmmaker turned giddy with so much artistic freedom. It’s like an Italian fashion magazine you never stop paging through (or the longest Madonna video ever made), filled with forbidden delights, such as the sight of young nuns disrobing and dancing to this season’s throbbing new theme song (“Good Time Girl” by Sofi Tukker featuring Charlie Barker, one of many ace picks on the show’s playlist) as their cloister house pulses with colorful strobes. Their superior — a cigar-chomping little person in full habit — dances her own jig.

The director is similarly committed to conveying church corruption as something one senses rather than reveals, picking up on visual cues that range from the awkward to the sinfully repugnant to outright garish and menacing, all set against extravagant interiors and exquisite exteriors. Much of “The New Pope” seems to be a protracted homage to the lighting and framing of Stanley Kubrick and David Lynch.

So what happens? I’m still wondering.

Though Voiello aspires to be the next pope, the college of cardinals elects an easily intimidated Franciscan, who names himself Francis II and immediately goes on a power trip, bringing in a troop of enforcer monks to liquidate the Vatican’s wealth and give it all to the poor. Small wonder, then, that he mysteriously drops dead.

Voiello and his crew then travel to England to recruit their next hopeful popeful — Sir John Brannox (John Malkovich), who lives in a castle on the estate of his parents, the duke and duchess of something-or-other.

In the manner of his idol, Cardinal John Newman, Brannox has written deeply and popularly on spiritual matters. He lives the life of a pampered but deeply morose intellectual, yet his teachings on love — and what he has opaquely branded as a “middle way” for religious faith — have great appeal. Although Sorrentino doesn’t give viewers nearly enough information or reason to make any of this seem plausible, it’s a fait accompli: The cardinals overwhelmingly choose Brannox, who becomes Pope John Paul III.

From there, for the bulk of “The New Pope’s” episodes, we are adrift in Sorrentino’s puzzling lack of theme or plot. Malkovich drips his lines out like they’re the finest honey, which is entertaining yet ultimately unimpressive, as an indifferent John Paul muddles through an agenda that seems primarily focused on meeting his favorite celebrities. These include Marilyn Manson, playing himself, a rock star so out of touch he has no idea who or what the pope is, and Sharon Stone, also appearing in a brief cameo as herself. (Stone tells the pope that it’s time for the church to approve same-sex marriage. “Can’t the Bible be upgraded?” she asks. “Alas, the Bible is not an iPhone,” the pope replies.)

Both “The Young Pope” and “The New Pope” thrive on strangeness and secrets — to a fault. In the first series, a viewer could encounter the more outré aspects of the narrative as a means of picking up on obvious themes: the mysteries of faith, the existence of miracles, the stress of believing. In the second one, everything’s just incrementally weirder and far less revelatory.

An intriguing subplot, pitting the Catholic Church against Islamic terrorists, fails to deliver on its building tension; the show insteads squanders time waiting for Pius XIII to symbolically rise from his medical tomb. Without spoiling it, I’ll just say the resurrection motif gets stronger as it goes.

In its final hour, “The New Pope” wraps up its story but still doesn’t get a handle on what all of this is supposed to mean. It may not matter at this point, as even the most faithful watchers will have lapsed into their own comas.

The New Pope (one hour) premieres Monday at 9 p.m. on HBO.