Downstairs at London’s Mayfair Hotel was Downton Abbey central this afternoon as ITV screened the show’s upcoming 2-hour Christmas Day special for the press. Several key cast members were there including Dan Stevens – who was just named a Man Booker Prize judge for 2012 and is starring in and producing Summer In February beginning next month – along with Brendan Coyle, Lesley Nicol and Rob James-Collier, among others. The Julian Fellowes-created show has become a phenomenon in Britain where it recently concluded its second season on ITV with a 21% uptick over the first, making it the most popular drama series on Brit TV in over a decade. (In the States, season 2 kicks off on PBS in January.) A 3rd series begins shooting on February 13 and will be set in the early 20s, but producer Liz Trubridge couldn’t give away many details saying they’d had just “a glimpse” of Fellowes’ first drafts. The 3rd season will also include a 2-hour telefilm, Trubridge confirmed to Deadline. Fans of the show (who, according to Siobhan Finneran – aka devious lady’s maid O’Brien – include Tom Hanks) should be mighty satisfied with the special screened today that takes place over a tumultuous holiday period in 1919. With regard to continuing the show, Trubridge told Deadline that it’s a wait-and-see game since commissioning is done at the end of the current season. “I’m sure we’d all want to do it,” she said. Coyle said the cast had been optioned only through 3 seasons and joked he wouldn’t mind a spinoff for his character called “Mr Bates Investigates.” Meanwhile, the busy Stevens said he might look for more producing projects depending on how Summer In February goes and told Deadline, “I’m just happy to be booked through October.”