Richard E. Grant as Simon Bricker and Elizabeth McGovern as Cora, Countess of Grantham in “Downton Abbey.” (Nick Briggs/Carnival Film & Television Limited 2014 for MASTERPIECE)

“Downton Abbey” has found its groove, which, of course, involves no real groove at all. A groove would ruin it. Viewers have figured out that their beloved British period drama moves through its stories like a perfunctory telenovela aimed at the whitest people alive and that the show is mainly a good excuse to dial back a century and watch the working class serve the 1 percent a formal dinner night after night after night — and pick up after them, and help them put on their clothes. (And to think we refer to shows like “Nashville” as “guilty” pleasures. What sort of penance must be paid for admiring the wealth gap at dear old Downton?)

Eh, it’s not worth getting political over — although “Downton Abbey” creator Julian Fellowes and his collaborators are the ones who bring it up loud and clear in this newest batch of episodes.

Season 5 begins its American airing on PBS stations Sunday night with the Crawley estate in a quiet dither over the election of Britain’s first Labor-affiliated prime minister. Upstairs, Robert Crawley, the increasingly defensive Earl of Grantham (Hugh Bonneville), is snapping at dinner guests who have the audacity to spout socialist leanings between courses; downstairs, aging servants, including the eternally beleaguered cook, Mrs. Patmore (Lesley Nicol), are dreaming of owning property in their retirement years.

Has the world gone simply mad? Only about a hundred times this season will one character or another mention that “things” are “changing,” to go with the few thousand references the show has already made to upheavals in social manners and class distinctions and other examples of what we in this century fashionably call “disruption.”

Downton is still years away from the disruption it so richly deserves; you’ll have to settle for Lady Mary (Michelle Dockery) showing off her new bobbed hairdo.

A full decade has elapsed in these five seasons (the series is now set in 1924), yet I keep hoping the show will catch a faster train and move ahead by a couple of decades. Imagine the Crawley toddlers, George and Sybil — soon to be fully joined by Lady Edith’s illegitimate daughter, Marigold — as young adults experiencing the drama of Downton during World War II. Imagine Downton’s existence in the Elizabeth II era and even later as a tourist trap. (“Who’s that strange old lady who lives in the attic?” “Oh, you mean Lady Mary? Tragic story, I’m afraid.”)

Instead, we are stuck here in this particular Downton, where everyone seems to be suffocating, and understandably searching for the most graceful exit. (Has it become a show about a prison? “Gilt Is the New Black?”)

Good manners necessitate several spoiler alerts from this point forward, even though it’s difficult to keep a lid on “Downton Abbey’s” plot lines these days, once Grandma figured out how to surreptitiously download the British airing three months before PBS’s airing. Anyhow . . .

Upstairs: Mary still can’t decide between two suitors asking to be her new husband, though she’s leaning toward Tony, a.k.a. Lord Gillingham (Tom Cullen). She’s interested enough that she sends Anna Bates (Joanne Froggatt) out the druggist’s to purchase a sex-advice manual and birth control device that everyone seems too afraid to refer to by its proper name (let’s go with “Beetlejuice”). After secretly spending a romantic week’s vacation with Tony (and Beetlejuice) all over England, Mary returns a tad underwhelmed.

Downstairs: Scotland Yard is still sniffing around the details of the sudden death last season of Lord Gillingham’s valet, who, while visiting Downton, brutally raped Anna. Her husband, Mr. Bates (Brendan Coyle) is still a prime suspect — until the case makes a sudden and certainly hokey swerve in the season’s penultimate episode, leading to the most mild sort of cliffhanger.

Upstairs: Tom Branson (Allen Leech), the former chauffeur who married into the family and is now, with Lady Mary’s input, the best hope for its financially sound future, wants out more than anyone who lives at Downton — upstairs or down. He mentions leaving for Boston in practically every scene he’s in, delivering the exact sort of lines written for an actor who isn’t interested in a contract renewal.

Downstairs: Same goes for Daisy (a.k.a. Never-You-Mind-That-Daisy, a.k.a. Get-Back-to-Work-Daisy), the young assistant cook (played by Sophie McShera). She smells revolution in the air and has hit the books to better her mind and better her employment chances.

Upstairs: Regretting the decision to give her secret love child to a nearby farm family, Lady Edith (Laura Carmichael) is hatching a mother-daughter escape plan.

Downstairs: The house’s most loyal servants, Mrs. Hughes and Mr. Carson (Phyllis Logan and Jim Carter), are inspired by Mrs. Patmore’s house hunting; now they’re thinking about buying a bed and breakfast together and bidding Downton farewell.

Upstairs: Even the Labrador has had it! (“Is something wrong with poor Isis?” family members start asking in foreboding “Downton Abbey” style.)

So if all these characters want to get away from Downton, why do so many of us still want to get in?

Oh, that’s easy. “Downton Abbey” doesn’t meet any objective criteria for brilliant television except for one: escapism. The castle, the clothing, the details, the fuss. The characters may weary of it, but the fans don’t.

The misery that “Downton Abbey’s” characters endure barely qualifies as misery when held up to the woes of other characters on other TV shows — and that, too, is a selling point. Their mild dissatisfaction is our idea of pleasure. Their little arguments and deceptions are like music to our ears. There has always been something delightfully passive about watching “Downton Abbey,” and there still is. The difference is that the clocks are ticking just a little more loudly now as everyone in the castle marks time.

Masterpiece: Downton Abbey

(75 minutes) returns Sunday at 9 p.m. on WETA and MPT. Continues through March 1.