In the HBO drama “The Gilded Age,” the characters are keenly aware that they live in interesting times. Early in the series, which is set in the eighteen-eighties, an estate lawyer observes that million-dollar fortunes are made and lost by the day in the railway business. One of its titans, the robber baron George Russell (Morgan Spector), envisions an express line that will enable cross-country transport at an unprecedented pace. Thomas Edison makes real the once fantastical notion of an entire building lit up by electricity, and Oscar Wilde charms the New York aristocracy with his witticisms, if not his plays. The promise in the air inspires immigrants, unionists, suffragettes, and a rising Black bourgeoisie. But though “The Gilded Age,” which returned for its third season on Sunday, alludes to all of these historical developments, it’s primarily occupied by the social-climbing efforts of George’s wife, Bertha (Carrie Coon), who’s hellbent on dominating Manhattan high society. Although an entire city beckons, the first season hinges in part on whether the Russells’ neighbor—the huffy, old-money Agnes Van Rhijn (Christine Baranski)—will ever cross Sixty-first Street to visit.

The phrase “the gilded age” is borrowed from Mark Twain’s 1873 novel of the same name, a political satire about the materialism and corruption of the years following the Civil War. The era is frequently invoked to explain the skyrocketing inequality of our own time. But the creator of “The Gilded Age,” Julian Fellowes—whose earlier period drama, “Downton Abbey,” drew criticisms as a rose-colored apologia for the British aristocracy—is single-minded in his focus on the loveliness of the veneer. It’s hard to think of another series currently on the air as lavish, or as vacuous. A businessman’s quip that banks are like women—they “panic at the unimportant and ignore the essentials”—is supposed to scan as boorish but inadvertently summarizes many of the show’s story lines. Plenty of series have managed to make frivolity feel meaningful, or at least fun. But so little actually happens, episode by episode, that “The Gilded Age” scarcely qualifies as a soap opera: by the time the Russell and Van Rhijn butlers begin passive-aggressively debating the placement of salad forks and coffee spoons, it’s clear we’re meant to feast on scraps.

Part of the problem is that there have been no real stakes to the proceedings. Other series about the ultra-wealthy, such as “Succession” and “The White Lotus,” illustrate how money cannot protect against emotional (or even physical) harm; if anything, the characters’ riches make them more vulnerable to it. “The Gilded Age” takes place during a time of extreme flux, and the variability of its characters’ fates is meant to be central to its premise. The expectation is set early in the series, when an alderman who tries to swindle George bankrupts himself in the process, then kills himself in shame. But nothing so consequential has happened since—if ruin ever looms, it doesn’t stick. Toward the end of the second season, for example, Agnes’s son, Oscar (Blake Ritson), loses the family fortune. Oscar, who is in the closet, has spent the series seeking a wealthy heiress through whom he can maintain his life style; the woman he chooses turns out to be running a scheme of her own, with disastrous repercussions for the Van Rhijns. His widowed mother suddenly faces the prospect of selling her home and living out her final years with her sister, Ada (Cynthia Nixon), in dire straits, while her household staff are left to fend for themselves. The twist is one of the show’s few satisfying developments: comeuppance for a would-be conniver! And then, in the next episode, through an inheritance bequeathed to Ada out of the blue, the family’s money troubles are instantly over. Agnes and Ada’s niece exults that “nothing needs to change.”

The series is not entirely unaware of its characters’ myopia. In the first season, Bertha focusses on the minutiae of her daughter Gladys’s entrée into society while her husband faces the possibility of imprisonment, and the previously uxorious George finds her increasingly ridiculous. In the new season, when Bertha believes that she’s found the right match for Gladys—an English duke whose old-world title would give the new-money Russells a social trump card—she acts more like a madam than a mother, icily dismissing the girl’s feelings in order to close the deal. But Fellowes refuses to treat it as a heel turn, even clumsily transforming Bertha into a proto-feminist who picks a fight about female suffrage at a dinner party and risks her own social status to advocate for divorced women. The attempted redemption arc never quite rings true.

It doesn’t help that Fellowes reaches repeatedly into the same small bag of tricks. Even with Baranski’s flawless line readings, there are only so many times we can expect to be amused by Agnes dubbing things “fiddle-faddle” or “hobbledehoys,” or being scandalized by, say, the newfangled prospect of hot soup for lunch. She’s an obvious successor to Maggie Smith’s Dowager Countess on “Downton,” and not the only retread that reaches a point of diminishing returns; the upstairs-downstairs contrast was key to the earlier show’s appeal, but the secrets that are forever being tearfully confessed by the servants of “The Gilded Age” are no substitute for inner lives. (Denée Benton’s Peggy, the sole Black lead, is the only member of “the help” to stand out, but she travels so far afield of the Manhattan and Newport enclaves where the rest of the series is set that she often feels like she’s on a different show.) On the higher floors, engagements are made and broken with the regularity of a Swiss clock.

In this season, though, consequences arrive at last. It’s not a coincidence that it’s the series’ strongest. Seeds planted at the outset are coming to fruition—most significantly, Bertha’s pitiless ambition leading to the formerly unthinkable crackup of the Russell marriage. Across the street, the foundations of the Van Rhijn home are also shaken after Ada’s unexpected windfall enables her to challenge Agnes as head of the household. These plotlines deliver on the anything-goes unpredictability that the show had initially promised: “The Gilded Age” won’t force any of its characters to relinquish the gilt, but their luxurious environs are now the backdrop for more serious woes.

Fellowes is even letting some of these characters evince more complicated emotions. Late in the season, an irreversible calamity does strike: one of Oscar’s lovers is killed, and he’s left unable to express to his family the extent of his grief because he cannot reveal the nature of their relationship. Even after the arc resolves itself, the rawness of his sorrow lingers. For all the references to real-life personages and historical events, this fictional beat is one of the few times when “The Gilded Age” offers genuine insight into what it must have been like to live in such an era. The rest is fiddle-faddle. ♦