Downton Abbey 604 spoilers
Gwen (Rose Leslie) sits down with Robert (Hugh Bonneville) in "Downton Abbey" Season 6, episode 4. Nick Briggs/Carnival Film & Television Limited 2015 for Masterpiece

“Downton Abbey” is welcoming a familiar face in Season 6, episode 4. The synopsis and trailer reveal that Gwen Dawson (Rose Leslie) will return. The actress has been busy starring in shows like “Game of Thrones” and “Luther,” but as previously reported, made a special appearance in the PBS drama’s final season.

“A former maid comes to lunch,” the synopsis teases. The trailer reveals that it’s Gwen, but don’t expect her to hang with the downstairs staff. Her reasons for returning have nothing to do with her friends.

While Gwen reunites with the Crawleys, the women currently working at Downton have plenty of their own problems to deal with. Anna (Joanne Froggatt) will have a much more pressing problem. “Anna and Mary [Michelle Dockery] rush to London,” according to the synopsis. Last time they were in London, they saw a doctor who said a simple surgery could prevent Anna from having another miscarriage. Will they make it to the city in time to save Anna from another heartbreak?

Downton Abbey 604 spoilers
From left: Lady Edith (Laura Carmichael), Isobel Crawley (Penelope Wilton), Anna Bates (Joanne Froggatt), Baxter (Raquel Cassidy) and Aunt Rosamund (Samantha Bond) celebrate in "Downton Abbey" Season 6, episode 4. Nick Briggs/Carnival Film & Television Limited 2015 for Masterpiece

She isn’t the only one in trouble. “Miss Baxter [Raquel Cassidy] faces a dilemma,” the summary says. Her past has come back to haunt her in a surprising way.

Elsewhere, Daisy (Sophie McShera) will keep fighting for Mr. Mason as she “continues to press her case.” She wants Mr. Mason (Paul Copley) to take over Mr. Drewe’s (Andrew Scarborough) position. It seems like the perfect opportunity, but it’s more expensive than other options. Will money be the deciding factor or will the Crawleys help Mr. Mason out?

“Car talk is in the air,” the synopsis also warns. Why is this important? Well, if you remember Henry Talbot (Matthew Goode), Mary’s love interest from the Christmas special, then you’ll know that he is a race car driver. Mary hasn’t had the best luck with men and cars, but will his job drive her away from him?

Watch the trailer for “Downton Abbey” Season 6, episode 4 below:

“Downton Abbey” Season 6, episode 4 airs Sunday at 9 p.m. EST on PBS.