Downton Abbey will return to ITV1 for a fourth series in 2013.

ITV has confirmed that filming of eight new episodes for autumn 2013 plus an extended special episode for Christmas 2013 begins at Highclere Castle and Ealing Studios in February next year.

The opening and closing episodes will again be feature-length, with series four continuing the story of the Crawley family and their servants in the early 1920s.

Laura Mackie, director of drama at ITV, said: “We’re thrilled to welcome back a drama series that has become a much anticipated part of all our lives every autumn and achieved success around the globe.

“Creator, writer and executive producer Julian Fellowes and the production team, led by Gareth [Neame, Carnival Films] and the producer Liz Trubridge, never rest on their laurels and have exciting plans for the fourth series.”

Before that though, fans will enjoy a two-hour special to be screened on ITV1 at 9pm this Christmas Day.

Laura said: “Last year’s special episode set the nation talking on Boxing Day and 2012’s Christmas Day episode is no different. As ever, Downton will take its audience through a whole range of emotions. All of life’s experiences will feature in this episode.”

It sees Lord and Lady Grantham and family heading for a summer break in the Highlands of Scotland, leaving most of their servants back at home.

The annual visit to his Scottish cousins at Duneagle Castle, where the piper calls the tune for breakfast and dinner, is the annual highlight for Robert (Hugh Bonneville) year.

Duneagle is the home of young, headstrong Lady Rose (Lily James), who was sent home in the last episode of series three after her dalliance with a married man.

The castle is an even more lavish step up from Downton, with deer stalking and fishing also on hand in the stunning surrounding Scottish countryside.

During the Christmas Day episode Lady Edith (Laura Carmichael) discovers that newspaper editor Michael Gregson (Charles Edwards) also happens to be on holiday in Scotland and may not be there just for the sketching and fishing. Matthew (Dan Stevens) and Mary (Michelle Dockery) disagree about Mr Gregson’s motives towards unlucky-in-love Edith.

Personal servants John Bates (Brendan Coyle), his wife Anna (Joanne Froggatt), Molesley (Kevin Doyle) and O’Brien (Siobhan Finneran) accompany the family on their trip north.

O’Brien discovers a kindred spirit below stairs in the form of her opposite number, Susan’s lady’s maid Wilkins (Simone Lahbib). But who will be left reeling at the Gillies’ Ball?

Meanwhile back in Yorkshire, estate land agent Tom Branson (Allen Leech) has stayed behind at Downton with young daughter ‘Sybbie’.

In spite of the family’s attempts to integrate the former chauffeur into their world, he continues to live between the Crawleys and the servants below stairs. He’s still grieving for wife Lady Sybil, who died after giving birth to their first child.

Butler Mr Carson (Jim Carter) faces the task of keeping the household servants concentrated on their work polishing the silverware and cleaning the rooms.

But with the family away, minds begin to wander to other things – including the forthcoming Thirsk Country Fair.

“While the cat’s away, the mice will play,” explained executive producer Gareth. “The Granthams do not live at Downton Abbey 12 months of the year. They would go to London for the summer season and also go away on holidays like this.

“And when that happens the domestic staff of Downton would remain. What will they get up to while the family is away?”