It's the Christmas season and Doug and Carrie run into Father McAndrew who manages to talk Doug into signing up for a shift of guard duty for the church Christmas decorations, and Carrie is roped in to baking a cake for the annual church cake sale. While Doug is guarding the decorations, one of the fellow parishoners wife brings a thermos of hot soup to keep him warm in the cold winter weather. Doug isupset that Carrie doesn't do enough "wife stuff" for him. So, when Carrie says she wants to take a store bought cake to the sale, Doug insists she become more wifely, and bake one herself from scratch. Carrie has never baked a cake before, and discovers that it's much harder than she thought it would be. It's time for the sale, and they don't have a cake to take, so the two get creative, and take a couch pillow covered in frosting, hoping no one will notice.
Meanwhile, Arthur and Spence are busying trying to write a Christmas song.