S6, E3: Preparations for Mr Carson and Mrs Hughes’ wedding are underway, but a misunderstanding threatens the peace. Edith reconnects with an old acquaintance, who comes to her aid in an hour of need. Spratt has something to hide but Denker is hot on the trail, and Daisy jumps to conclusions about a plan of Cora’s. Tensions mount over the hospital takeover, leading Isobel to offend a friend. The wedding day brings a surprise, with the arrival of some unexpected guests.