It's the end of an era for Downton Abbey, both for the Crawleys and for the fans worldwide who've come to love them.

The British period drama won over viewers with its look at post-Edwardian England, when one's bloodline determined one's status, and the noble houses were run like clockwork by a fleet of dedicated servants. On Downton's upcoming sixth and final season, which premieres Jan. 3, that noble way of life is slowly but inexorably dying out.

"That was the trajectory of those houses," executive producer Gareth Neame tells TVGuide.com. "They didn't continue forever, they weren't financially viable. So in this final season, we will see the way of life we've all enjoyed watching in that show starting to change and evolve in a new way.

"We've got 20 or so main characters. There's a lot to get done in these final nine episodes," he continues. "This is ultimately a happy show that people love, so I don't think we're going to end with lightning striking the house and the house is exploded or something. But not everyone will have a happy ending."

Well, that sounds... ominous. Need more than that? Here's all we could glean about Downton's final outing so far, based on interviews with the spoiler-phobic cast and the PBS session at the Television Critics Association fall TV previews that presented a handful of sneak peeks.

[WARNING: The following contains mild spoilers. Read at your own risk!]

From weddings to fights: Scoop on Downton Abbey's final season

The Dowager Countess (Maggie Smith) "She's full of beans. She's on fire," Elizabeth McGovern says of Smith's grande dame character Violet this season. "From what I saw when we were shooting, she's at the top of her game." Neame adds, "She has to be the main commentator of everything that's going on in that show. I suspect she'll have lots to tell us in the very last episode."

Penelope Wilton, who plays Violet's cousin and confidant Isobel Crawley, says, "Violet and I are up to our old tricks. There's a lot of sparring that goes on this time." A clip shown during PBS' Downton panel on Saturday reveals the two friends on opposite sides of a debate relating to the hospital, battling over power versus patients.

This hint by Hugh Bonneville could explain the nature of their disagreement: "There's a sort of microcosm debate about health insurance, for want of a better word, or the way that health is managed. We do get to meet the Minister of Health, who is a real person and a significant character in later British life."

Lord and Lady Grantham (Hugh Bonneville, Elizabeth McGovern) At least the art appraiser who admired Cora appears to be out of the picture this season. "In terms of [Robert and Cora's] relationship, I think it's fair to say that we're back on an even keel after some bumps," Bonneville says. "But Cora has a cause in mind and wants to strike out for a bit of independence and give herself a bit of activity outside of the house, which makes Robert feel a bit of, 'What am I going to do then?'"

"Cora is becoming more slightly a modern woman and defining herself as separate from family and Robert in a slight way," McGovern says. "She's always the one to ease old feet-in-the-clay-Robert into the modern world. So she still does a bit of that. In very touching ways, he does allow this to happen."

He doesn't have much choice though. The eventual elimination of the landed gentry "is brought home to us when we go visit a local landowner who's having to sell up," says Bonneville. "So it's really about that -- a creeping sense of doom for estates like Downton. Either adapt or die."

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Lady Mary (Michelle Dockery) The Crawleys' eldest daughter played with at least one man's heart last year. Remember when she dumped poor Gillingham and then afterward appeared at the hunt looking spectacular? Well, watch out, because she rides in yet another hunt in the first episode back. Perhaps she wants to impress car aficionado Henry Talbot (Matthew Goode), whom Bonneville confirms returns this season. Whether he has a chance to succeed Matthew in Mary's heart remains to be seen however.

"To use modern parlance, she's gone on a few dates, but that's inconclusive," Neame says. "I'm interested in exploring this territory because she's older than she was in the early seasons and she's been married and she's a widow. For anyone who's been divorced or widowed, entering into a second marriage is so much more complicated than an initial relationship. It's much more complicated."

When Mary isn't plaguing the men, she's of course locking horns with her only surviving sibling. "There's a great argument between the sisters, Lady Edith and Lady Mary," Joanne Froggatt reveals. "They've sort of mellowed a bit over the years, but this is a reminder of how things were. I can't say what it's about, but it's great. Everyone's going to be, [Gasps] 'I can't believe she actually said that!''"

Lady Edith (Laura Carmichael) Speaking of poor Edith (really, she may as well be called that), she is now the owner of her lover Gregson's newspaper, which is a challenge for any woman, let alone for, um, poor Edith. "We'll see how the men of the 1920s take to being told what to do by a woman," Carmichael says. "She remains a kind of contributor, and there is an editor, Mr. Skinner, who we meet in the first episode. He's a nightmare, so yes, it's a question of can she work under him?"

Edith's absence from Downton to take care of business in London does not go unnoticed by her sister, who is the only close family member who does not know or suspect that young Marigold is Edith's actual love child. "I think Mary thinks that she's made this rather odd Edith-like decision to adopt this orphan child and finds her more hands-on parenting as another way to annoy Mary," Carmichael explains. "Mary is not interested and wants to prove the point that she's not interested by not investigating her odd behavior."

As for her love life, Lady Edith isn't on the hunt like Mary (even if she did have a nice moment or two with that Brancaster land agent Bertie last season). "She says she's looking middle-aged in the face," the actress says. "She's like, 29. It's terrible! But it's a '20s thing of feeling [older] because they came out when they were 16. She's on the shelf! So for her it's not on her mind, but I think she needs someone who's going to challenge her and accept her."

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Isobel Crawley (Penelope Wilton) "She has quite a roller coaster of a ride. You don't really know what's going to happen to her in the future until the very end of the series," Wilton says about Isobel this season. She might be referring to Isobel's failed romance with Lord Merton (Douglas Reith), whose proposal of marriage she had accepted and then eventually turned down after his sons snubbed her for being born middle class.

"Lord Merton is still on the scene. I think he's always going to be interested," confirms Wilton. In a clip shown at the fall preview panel, Lord Merton points out that they're on the same side in the debate with Violet, but Isobel coldly tells him not to make too much of it. Ouch! Wilton notes, "It's a complicated relationship that grows even more complicated as the series goes on."

Tom Branson (Allen Leech) Yes, the former chauffeur had the gall to move to America with his daughter Sybbie. "He goes to open a car showroom," Bonneville confirms. "But put it this way, not everyone loves him living in America." In a clip shown at the PBS panel, Mary tells Anna about a letter in which he very clearly misses Downton, which indicates he'll probably return before the show wraps up for good. Anyway, we've all seen these photos, yes?

Mr. Carson and Mrs. Hughes (Jim Carter, Phyllis Logan) The heads of the household staff got engaged in last year's Christmas episode (a far better Christmas tradition than, let's say, killing off a main character), but Carson isn't comfortable enough to call his fiancée by her given name in public yet.

Nevertheless, it's clear their engagement news has led to wedding plans, judging by a conversation between Lady Mary and Anna about wedding dresses. Neame says, "A proposal has been made, but where that leads we'll have to see." Ugh.

Bates and Anna (Brendan Coyle, Joanne Froggatt) Meanwhile, the most put-upon married couple will have to struggle a little longer with the murder of Anna's rapist Mr. Green, whose despicable act makes us hate that he's still a presence on the show despite his untimely end. "There's still this police investigation. That has to be resolved one way or another," Neame says.

Froggatt offered a little bit of hope: "There is happiness for Anna and Bates, but it's not easily attained. They just have more problems thrown their way this year, a whole new set of problems that we didn't even know about. Yes, so there's a new challenge for Anna and Bates."

The actress wouldn't reveal whether or not the couple would expect a baby Bates this year, but if they did, at least they could support the child. "Their roles are sort of imperative to the running of the house, really," Froggatt says. "Anna is Lady Mary's lady's maid obviously, and she's been with her all her life. She's not going to lose her job. Same for Mr. Bates."

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Daisy Mason (Sophie McShera) Daisy turned down a chance to go to America last year, but that doesn't mean she's given up on all the changes she's made for herself through her studies. "I think the main theme that stands out for me ... is the sort of social mobility of the working classes," Froggatt notes. "We see it with Sophie McShera's character Daisy that she's educating herself and she's wanting to do her exams. That's because she eventually wants to manage her father-in-law's farm." In one of the clips shown by PBS, we see Lady Cora counseling Daisy about Mr. Mason, who has been kicked off his farm.

Mrs. Patmore (Lesley Nicol) The head cook was thrilled Daisy wasn't going to leave after all last season, but this year, Mrs. Patmore is back to her grumbling ways. "[Daisy's education] makes the scenes with her and Mrs. Patmore that more fun," Carmichael says. "It's like, 'Have you swallowed a dictionary?' Mrs. Patmore's gibes come in droves. It's wonderful." The cook will also have to start using Downton's very first refrigerator!

Thomas Barrow (Rob James-Collier) The PBS panel played what appeared to be old clips of Thomas buddying up with the footman Andy against Denker last season, which was odd and made us afraid that maybe our favorite scheming underbutler would get short shrift this year. Not so. "He has got a number of compelling things going on in this next season," Neame says. No more details than that, but we'll take it!

Familiar faces Who -- besides the dead -- could return to the show for its final hurrah? "There were a couple characters that were teed up towards the end of last year who make a welcome return," Bonneville says. But McGovern adds, "You'll see a lot of the characters that you met in the first season. So for true aficionados of the show, it's really on because you see that person that you don't know quite what happened to them. I absolutely love that about the last season." Any guesses? We hope to see Gwen (Rose Leslie), Alfred (Matt Milne) and of course, O'Brien (Siobhan Finneran).

Who you won't see Sorry, but Cora's American family won't be visiting again, but, "we do get a letter from mum at the end," McGovern says.

Who's dying It stands to reason that someone will be buying the farm (not Mr. Mason's) this season. After all, the show hasn't hesitated to kill off main characters (or even Isis the dog!) when necessary. "It's always a possibility," Neame says. We just want Violet to live forever!

Downton Abbey's final season returns to on Sunday, Jan. 3 on PBS' Masterpiece.

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