After Matthew's death, Mary fell into a long period of depression. She did nothing every day, and it seemed that her soul had died with Matthew. However, the pace of time will not stop because of anyone's sadness. Downton is still the busy Downton upstairs and downstairs. Robert, the head of the family, still has to worry about Downton's revenue, and the old lady also has to care about her granddaughters. The second lady is still looking for her happiness, Tom is gradually integrating into this big family, and Matthew's mother must also get out of the pain of losing her son. Thomas is still making waves in the servants' world, and he seems to have not learned the previous lessons; the feelings of several maids and male servants are also entangled, and even Anna and Bates's relationship is not smooth sailing... With the progress of the times, Downton's backward manor management methods need to be changed urgently. Can Mary inherit Matthew's will and continue his unfinished business? And in the face of the pursuit of others, what choice should Mary make?