As Tom and Sybbie settle back into life at Downton, the family and servants are surprised with the return of another old friend in unexpected circumstances. A visit from Sergeant Willis leaves Baxter with a dilemma, and Thomas struggles to fill Mr Carson’s shoes. A crisis takes Anna and Mary to London; will Bates find out what Anna has been keeping from him? Daisy has a bone to pick with Cora, and Mary’s eye is caught by an admirer.