When "Downton Abbey" returns this Sunday, the Crawley family will be mourning yet another untimely death. 

While the beginning of the season will start off on a sad note, three potential suitors will help lift Mary out of her depression. One of the suitors is an old family friend, Gillingham (played by Tom Cullen); another is a newcomer, Blake (Julian Ovenden); and the third is the Turk's friend Evelyn Napier (Brendan Patricks). 

Michelle Dockery spoke to TVLine about what's in store for Mary this season. 

Dockery said Mary will not immediately start seeing other men, as she is still grieving over the devastating death of her husband. 

"You can't suddenly see Mary with another man immediately after Matthew because the audience invested so much in that character and that storyline between Mary and Matthew. It would just be wrong for her to move on quickly," she said. 

Dockery also said that Mary will not spend a lot of time with her child, but explains that it was the aristocratic custom at the time. 

"She's an aristocrat. She has a nanny," Dockery laughed." "You don't see a lot of her with the baby because that's the way it was then. She's very practical. I don't think she was ever going to be a doting, cooing mother. At the beginning, it's difficult with the baby because she looks at him and she sees Matthew. She's just adjusting."

This season, Mary will become better friends with her brother-in-law and fellow widower, Branson (Allen Leech). However, Dockery ensures that Mary and Branson will not become an item. 

She also said that Paul Giamatti, who plays Mary's uncle, will be a "slightly caddish, player type."

Additionally, she shared that "Downton's" Christmas special will be a bit more optimistic this year, without a tragic ending. But she said the "unexpected twists and turns" is what makes the show appealing. 

"One minute, you're laughing. The next minute, you're crying. It's very rich with story," she shared.

Season four will also see the characters stepping wholeheartedly into the gaiety of the 1920s.

"It feels like a burst of energy midway through the fourth [season]," she explained. "It feels very much like you're in the heart of the '20s, the roar of the '20s. And the costumes are evolved even more. They're very, very '20s. The flappers are coming in. The dances have changed. They're faster dances. It breathes that whole era."

"Downton Abbey's" fourth season premieres Sunday, Jan. 5 at 9 p.m. on PBS.