Spoiler alert! The following post contains details of the series finale of HBO’s “The Regime” (now streaming on Max).

On Sunday, Kate Winslet’s political satire “The Regime” reached its tragic, violent finish.

But as the Oscar winner tells it, it may have been the series’ most rollicking episode to film. After her palace is stormed by rebels, mercurial dictator Elena Vernham (Winslet) goes on the lam with her ruthless bodyguard-turned-lover Herbert Zubak (Matthias Schoenaerts). At one point, they hitchhike with an old drunk named Tomas (Karl Markovics), who swerves down dark roads blasting Christmas carols.

“There are many, many outtakes, I’m ashamed to say, of Kate and Mattias doing quite a lot of giggling, especially in Episode 6,” Winslet recalls. “Oh my God, everything in the back of the car. When I’m going, ‘Tomas, my love,’ and being obsessed with this idea of trying to find a phone, that was all middle of the night, freezing cold in England, cramped as all hell and just making stuff up. Honestly, that’s what the script gave us: the scope to experiment and really play.”

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Elena and Herbert quickly learn that Tomas is not their friend. After arriving at Tomas’ house, he locks them in his basement and waits for the insurgents to arrive to claim a bounty on the detested chancellor. But Elena is ultimately rescued by government officials, who promise she can return to power as long as she makes some key changes to how she rules. Most devastating for Elena: She must return to her husband, Nicholas (Guillaume Gallienne), and get rid of Herbert.

The tempestuous couple spend one last emotional night together before we see a faint glimpse of Herbert shot dead. In the show’s final scene, Elena is back in her seat on the throne, with Herbert’s body in a nearby glass coffin (just like her nightmarish father in the series premiere).

Their love story is both toxic yet very traditional, says Will Tracy (“Succession”), who created the six-episode series.

“It’s opposites attract, but it’s also two people who, at least for glimmers of the show, are helping each other become the best versions of themselves,” Tracy says. “In some ways, it’s the larger geopolitical story of the show that prevents them from becoming an actualized, healthy partnership. She’s broken in many ways, but one of them is her fame and power and isolation. It’s poisoned her mind, and by turn, she poisons this system of government that Zubak is a product of. He’s been abused by the system she created, so it’s never going to work.”

More shocking than Herbert’s death is that of Agnes (Andrea Riseborough). Elena’s right-hand woman was shot by rebels during the palace raid at the end of Episode 5. Agnes was, in some ways, the audience's surrogate: She no longer wanted to take part in Elena’s tyrannical reign but felt pressured to stay to protect her young son.

Agnes is “a fascinating and heartbreaking” character who represents the working class, Riseborough says. “She is consumed with the mission to keep her son alive. She’s in a situation where she’s morally compromised, but she’s also complicit. She’s part of this enormous machine she hasn’t left.”

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In the final scene, Elena puts flowers on Herbert’s casket, as Chicago’s “If You Leave Me Now” plays and the end credits roll. It’s a callback to the first episode, when Elena shrilly performed the song at a state dinner.

Although the series is set in a fictional European country, Tracy was keen to sprinkle in schmaltzy American pop culture. Earlier in the season, there’s an amusing scene of Elena and her husband solemnly watching an episode of “Friends.”

“I was really interested in this idea that this person who’s in the midst of a fervid, anti-American rhetorical campaign might go home at the end of the day and watch the epitome of the mainstream American sitcom,” Tracy says. “There’s some truth to that. I mean, even when they found Osama bin Laden holed up in that compound, he had American movies he had downloaded on his computer.”

If Elena seems unlike any character you’ve seen on TV before, it’s because she is. She was initially conceived as a man, but Tracy flipped the gender as a writing challenge and to open up new possibilities.

“We usually see this kind of strongman, brutalist interpretation of what a dictator is, especially in American fiction,” Tracy says. “I just thought, ‘Wouldn’t it be interesting if it was someone who used that maternal warmth and emotional accessibility as not only a weapon, but a marketing tool?’ She uses those optics to her advantage and gets away with some very bad behavior. Until she doesn't.”