Netflix’s “The Crown” returns for a third season in topmost form Sunday after a wait of two years, which is still not as long as the wait for some kind of solution to Brexit. It has a smashingly good new cast (whose performances are equal to if not better than their predecessors’) and a brisk, almost urgent sense of galloping through the long life story of Queen Elizabeth II.

As before, it’s a show to savor — every drop of it. Ten episodes, opening a few months before the death of Winston Churchill in 1965 and ending with the queen’s 25th jubilee in 1977, can easily seem like never enough, even when a couple of episodes start to wheeze toward the end.

Played by Oscar winner Olivia Colman (“The Favourite”), this queen becomes the far more recognizable stalwart, the stiffest upper lip in the United Kingdom, so sparing in her interactions that even she wonders whether she might have some sort of social anxiety disorder. She fantasizes about a life in which she has to care only about her racehorses. As envisioned by creator Peter Morgan and his team, “The Crown’s” greatest strength is the way it richly imagines those private moments that no one ever saw. We’re here because the suffering is so rarefied. Oh, these poor, poor souls who must go their entire lives doubting their God-given right to a cloudy day.

While England grapples with a worsening economy and overall malaise, midlife gloom is the main bugaboo for the occupants of Buckingham Palace, made evident as the first episode opens with Elizabeth’s chance to examine the updated profile of her that will grace the new postage stamps.

Despite every assurance from her advisers that her maturity is a thing of beauty, the queen is not convinced. “One just has to get on with it,” she says. Inheriting “The Crown” from Claire Foy (who won a Golden Globe and an Emmy for playing the role in Seasons 1 and 2), Colman is convincing in the role from the moment we see her, conveying the queen’s deepest worries with just the slightest twitch.

The bigger surprise is Tobias Menzies (“Outlander,” “Game of Thrones”), who takes the role of Prince Philip, previously played by Matt Smith, just as the royal husband’s story gets a bit deeper and darker. Philip’s midlife crisis — triggered in part by his envy of the American astronauts who land on the moon — is a study in the fragility of male ego.

He is also jangled by the sudden presence of his elderly mother, an orthodox nun (scene-stealer Jane Lapotaire) once known as Princess Alice of Battenberg, who found solace from mental illness and emotional demons by devoting her life to charity. After a military coup in Greece, the palace brings an ailing Alice to stay, over Philip’s objections. He warms to her once he sees that the press adores her, dubbing her “the Royal Saint.”

Public perception becomes a central preoccupation for the Windsors. A day-in-the-royal-life BBC documentary, meant to humanize the family, is generally regarded as a dud by those who watch it, especially the queen herself.

It’s Princess Margaret, the queen’s increasingly dissatisfied sister (now played by Helena Bonham Carter), who possesses the true gift for limelight. On a trip to the United States, Margaret scores big with the glitterati in San Francisco and L.A. Her celebrity, though greeted with quiet disapproval in the palace, is also seen as an asset — so much so that Margaret is diverted to Washington to charm President Lyndon B. Johnson (Clancy Brown), who has taken a chillier view of U.S.-British relations than President John F. Kennedy did.

Margaret’s messiness continues to be one of “The Crown’s” primary fixations: her inebriated tirades; the slow collapse of her marriage to Antony Armstrong-Jones (Ben Daniels); the ceaseless ennui of a pampered life at a price point that fuels anti-royal sentiment. Bonham Carter aces the tantrums and the shrewd deployment of iciness, but, after a strong second episode titled “Margaretology” (which includes her American escapade), Margaret’s aimlessness becomes tedious. Bonham Carter’s performance is capable, but not exactly memorable.

The queen, meanwhile, has one of her earliest reckonings with class and human suffering in the modern era, as she wrestles with an appropriate royal response to the tragic deaths of 144 people, mostly schoolchildren, in the 1966 slurry avalanche at a coal-mining site in Aberfan, Wales. It’s a foreshadowing, of sorts, of the delayed royal tears after Princess Diana’s death three decades later, depicted so memorably in Morgan’s screenplay for the 2006 film “The Queen.”

“What precisely would you have me do?” Elizabeth asks, when the left-leaning prime minister, Harold Wilson (Jason Watkins, whose performance is one of this season’s highlights), suggests that her majesty visit the site, as bodies are still being recovered.

“Comfort people,” Wilson says.

“Put on a show?” the queen says. “The crown doesn’t do that.”

“I didn’t say put on a show,” Wilson replies. “I said comfort people.”

Attempts to interest us in young Prince Charles’s special burden of duty and destiny fall a little flat. Josh O’Connor (“The Durrells in Corfu”) tries to help us relate to Charles’s dour semester spent learning the native tongue in Wales, in the weeks leading up to his investiture as the Prince of Wales. A patient professor (Mark Lewis Jones) opens the heir-apparent’s eyes to class struggle, which Charles views from a perspective that differs from his mother’s.

Charles’s misery drags on, as he meets and falls in love with Camilla Shand (Emerald Fennell), only to have the romance thwarted by the family. Obviously “The Crown” is obligated to treat this burgeoning drama as the real meat of the matter, seeing as how the relationship stood the test of time and affected so much else yet to come, but something about the story — the way it’s written, the way it’s performed — takes a viewer out of whatever spell the series usually casts. It’s more like a Lifetime movie.

It helps immensely that Morgan and company, who aren’t complete sticklers about the timeline, weave Charles’s heartbreak in with the approaching death of David (Derek Jacobi), the former Edward VIII, who gave up the crown to be with the woman he loved.

In his fading, David reminds us: “The crown always finds its way to the right head.”

And that’s what keeps “The Crown” percolating, as it prepares for the tumult of historical events and tabloid scandals ahead. The show has a subliminal willingness to seed a constant doubt, to undermine age-old concepts of entitlement. It blends fact, fantasy and humanity in a way that allows us to wonder if the crown truly does rest where it ought.

The Crown (10 episodes) returns Sunday on Netflix.