Christmas is coming to Mapperton and Julie Montagu, Viscountess Hinchingbrooke is determined to create a gala yuletide celebration. Her mission begins with the hunt for the perfect tree on the grounds of her 2,000-acre estate, followed by a trip to the real Downton Abbey--Highclere Castle--to get some tips on turning Christmas into a revenue generator. She can't stay long though; there's still a 13-foot Norway spruce to decorate back at her own manor house, plus food to prepare, a church carol service to host, and a grand feast for 110 guests.