If you were hoping that Downton Abbey‘s culminating season (premiering Stateside Sunday, Jan. 3 on PBS) would usher in a time of sisterly peace and love, you might want to prepare yourself for a reignited competitive spirit between Mary and Edith.

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“They remain true to their relationship,” star Laura Carmichael says. “There is an element of respect and love there. It’s just frosted in the guise of bitterness. There’s a lot of that this season, because they’re both becoming these successful women in different ways.”

With Edith managing the paper in the city and Mary overseeing the estate at home, “they’ll be like, ‘Who’s got it better?'” Carmichael continues. “Edith’s living in a house that Mary’s now running, which doesn’t feel great for Edith. And Edith swans in and out to London, going to fancy this and fancy that. They have moments of being tied with their lot and envious of the other. Therefore, the rivalry sparks up again.”

As Mary throws herself into business mode, romance takes a backseat for the widow. “She’s enjoying looking after the estate and making decisions, much to Violet’s dislike,” leading lady Michelle Dockery says. “I don’t think Violet’s gotten used to her two granddaughters being working girls. Her bond with [son] George is strengthening. He’s her priority. So her romantic life is quiet in the beginning.”

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But then a familiar and very handsome face returns to remind Mary there’s hope of a happy ending. “Henry Talbot [played by Matthew Goode] comes back into her life,” Dockery reveals. “But it’s complicated, as it always is. It’s never plain sailing in her love life.”

Meanwhile, Edith is “staring middle age in the face, and she’s sort of written [love] off for herself,” Carmichael says. “But that doesn’t mean [series creator] Julian [Fellowes] has.”

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So what did the show’s creative mastermind gift the Crawley sisters with during the series’ swan song?

“Just when I thought it was coming to an end and wrapping up for Mary, Julian threw a cat among the pigeons,” Dockery teases. “There is a really great arc. It’s something I wasn’t expecting, and it’s really clever what he does.”

Adds Carmichael: “It’s a really satisfying ending. It’s hard. It’s never going to be the way that you think it is. There’s going to be a lot of gasps and tears, but all in that classic Downton way!”

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