In the aftermath of the Abbey's eventful party, Mary is forced to answer a pressing question about her future, while Carson reveals surprisingly intimate details about his former life. Rose's trip to the bright lights of London sees her risking the Crawleys' reputation, and Gregson shares ambitious plans with Edith, taking their relationship to another level.

A birthday party is planned for Robert, but Rose's surprise contribution to the event ruffles feathers above and below stairs. A new farming venture on the Downton estate comes with dramatic repercussions for Mary, and Edith receives more unwelcome news.