The Duchess of Cambridge was paying a Royal visit to the set of Downton Abbey at Ealing Studios in London. The princess, who confessed to being a fan back in 2011 fitted right in on set as she arrived looking even more regal than Lady Mary. The beautiful brunette was on set to watch a scene from series six being filmed much to the delight of the cast including Joanne Froggatt who tweeted an excited message before the Duchess's arrival.