'Downton Abbey' Christmas Special Spoilers: 5 Things to Know About The Finale Episode

The Christmas episode of "Downton Abbey" will be the official series finale. It will first air in the United Kingdom on Christmas Day, but viewers in the United States can watch it after the airing of the show's sixth and final season, which will commence in its American airing schedule on Jan. 3, 2016, per PBS.

So, what can viewers expect from the Christmas special and last episode? Here are five things:

1) Lady Rose (Lily James) will definitely make her appearance. For the most of the sixth season, Rose's presence was non-existent and she was only mentioned in one of the episodes as enjoying wedded bliss in America. But, for the holidays, Rose will be back and will likely be pregnant as well, according to The Telegraph.

2) Lady Mary (Michelle Dockery) and Lady Edith (Laura Carmichael) might finally bury the hatchet. The sibling rivalry between these two women has always divided viewers. The episode's synopsis indicated that there will be a build up to this storyline. "Mary endeavors to build bridges with her sister while Edith's secret continues to pose a threat, despite having nothing left to lose," the synopsis party read, per Spoiler TV.

3) Lady Edith's wedding could proceed. It's what fans of the series are hoping and there are assumptions that the writers will give a happy ending to this one, per Forbes.

4) Thomas Barrow (Rob James-Collier) could be leaving the estate. Based on the teaser released in early December, Barrow was seen bidding goodbye to his colleagues. He has been wanting to leave the Crawley house for quite some time to embark on a better job opportunity elsewhere.

5) The special will leave viewers a "wreck."  This was what the cast warned during interviews, but it's going to be happy tears for the most part. "It's going to work so well and it'll tie up all the loose ends. It's two hours, which is a bit of a killer on Christmas night when you're stuffed full of mince pies, but it's worth it," said Jim Carter, who played Mr. Carson, via Express.

"I turned straight to the last page to see how it ended and I thought it was entirely appropriate," said Hugh Bonneville, who played the Lord of Downton Abbey, in the same report. "All I can say is that when I read it, I choked up. I knew it was going to be the last episode I was ever going to read."

The "Downton Abbey" Christmas special will air on ITV on Dec. 25 at 8:45 p.m.