Also on the boiler in the Christmas special is the ongoing romance between rebel Lady Sybil and chauffeur Branson.

Actor Allen Leech, who plays the Irish driver, was thrilled when the pair finally kissed.

He says: “It is the scene everyone wanted to see.” And Jessica Brown-Findlay, who plays Lady Sybil, insists: “I think she and Branson are truly in love. They would have to be to make that leap.”