Penelope Wilton, left, and Maggie Smith in “Downton Abbey: A New Era.” Ben Blackall/Focus Features

Shameless fan service seems to be the defining characteristic of this summer’s biggest franchise films, with “Doctor Strange in the Multiverse of Madness” setting a high (or is that low?) bar in its effort to cater to die-hard fans of the Marvel Cinematic Universe at the expense of more casual viewers. The long-delayed sequel “Top Gun: Maverick,” which opens Friday, will follow suit in its desire to give devotees of the 1986 original exactly what they crave: naked emotionalism and fighter jets.

Similarly, this week’s “Downton Abbey: A New Era” – the second movie spinoff to the long-running TV soap about the ups and downs, romantic and otherwise, of a family of British aristocrats and their servants – opens with a double-wedding scene that sets the tone for several crowd-pleasing couplings that will soon follow. We are brought up to speed with the marriage of former chauffeur and widower Tom Branson (Allen Leech) to lady’s maid Lucy Smith (Tuppence Middleton), and the marriage of footman Andy Parker (Michael Fox) to cook’s assistant Daisy Mason (Sophie McShera).

These unions between sentimental-favorite characters will come as no surprise to anyone who saw the last film. And for those who didn’t, there’s a helpful prologue that accompanies “A New Era,” courtesy of footman-turned-schoolteacher Mr. Molesley (Kevin Doyle), who efficiently recapitulates the events of the tumultuous 2019 drama, in which a visit by the king and queen of England caused all manner of commotion, upstairs and downstairs, at the titular Downton. (All sequels should be so – there’s no other word for it – considerate of their audience.)

But these introductory love stories are mere appetizers to the main course of romantic intrigue on the menu of this savory, 1928-set souffle, which concerns the possibility of a week of passion, some 60 years earlier, between everybody’s true favorite, matriarch Violet Crawley, aka the Dowager Countess of Grantham (Maggie Smith), and a mysterious French marquis. No sooner has Molesley dispensed with his preamble than the Crawley family’s lawyer (Jonathan Coy) arrives at Downton with the revelation that the countess has been bequeathed a villa on the French Riviera by a recently deceased nobleman, apparently someone once besotted with Lady Grantham in the early days of her marriage.

Speculation runs rampant as to the nature and extent of this secret relationship, and whether the dowager countess’s son, Robert (Hugh Bonneville), might really be – quelle horreur! – half French. This bombshell precipitates a trip to the South of France by most of the Crawleys; it’s an utterly preposterous plot contrivance by series creator Julian Fellowes – necessary only as an excuse to vary the scenery. (And, by that measure, it’s a smashing success.)

Meanwhile, back at home, Robert’s daughter, Mary (Michelle Dockery), is left to oversee a movie crew that has rented out Downton for filming, in exchange for a fee that will cover repairs to the manor’s leaky roof. This also affords director Simon Curtis the opportunity for some comic relief: Minor characters wander onto the set as the camera is rolling, and the gorgeous leading lady (Laura Haddock) is discovered to have the squawking Cockney speaking voice of an Eliza Doolittle when the production switches gears from a silent film to a talkie. Flirtations occur, between certain members of the Crawley family and staff and two members of the film crew: its handsome director (Hugh Dancy) and the debonair leading man (Dominic West). The action of the story switches back and forth between the two locales, Downton and France.

The film’s subtitle refers most explicitly to the advent of talkies, which were just becoming a thing in the late 1920s. But “A New Era” has multiple other meanings as well, including the film’s message of gay tolerance (arguably somewhat anachronistic for the time). To the gay butler, Thomas Barrow (Robert James-Collier), whose storyline of unrequited love featured prominently in the last film, comes, at long last, the prospect of bliss. “I wish you all the happiness this cruel world can afford,” Lady Mary tells him, without acknowledging that she’s not really saying a lot.

But there are other dramatic closures, too, that signal not just the dawn of a new age but, inevitably, the end of an old one. The subtitle refers not only to the twilight of the 1920s but to a changing of the guard in this entertainment franchise as well. In that sense, maybe “Downton Abbey” isn’t really giving its fans what they want, but what they have always needed to accept in this epic saga: that time doesn’t stand still.