CARNIVAL Films, the producers of Downton Abbey, have announced details of the Downton Abbey Christmas episode.

It rejoins the family in the early autumn of 1924. The two hour episode will be shown on ITV at Christmas.

Joining the cast as a guest star is Alun Armstrong (New Tricks, Braveheart, Sleepy Hollow). Alun will play Stowell, the Sinderbys’ butler.

Also joining is BAFTA Award nominee, Jane Lapotaire (Blind Justice, Shooting Fish, There’s Only One Jimmy Grimble) who will play the much talked about Princess Irina, wife of Prince Kuragin (Rade Sherbedgia).

It's grouse shooting season and Rose’s father-in-law, Lord Sinderby, has rented out Brancaster Castle in Northumberland and invited the Crawley family to a shooting party.

While good sport is enjoyed, Stowell (Armstrong) has an axe to grind and a scandalous secret threatens to undermine the holiday.

Surprises are in store as the families become better acquainted with each other and some new faces arrive on the scene.

Meanwhile the servants hold the fort back at Downton. As Anna faces an uncertain future behind bars, Bates takes drastic measures in a bid to clear her name.

Baxter and Molesley are busy on a joint plan and Carson and Mrs Hughes consider a business venture.

Alnwick Castle, in Northumberland, was used as the location for Brancaster Castle. Production spent two weeks in Northumberland and filmed in the spectacular interior rooms as well as the incredible Hulne Abbey.

Making a return to Downton Abbey are James Faulkner and Penny Downie as Lord and Lady Sinderby, along with their son and Lady Rose’s husband Matt Barber as Atticus Aldridge.

Rade Sherbedgia will also reprise his role as Prince Kuragin and Michael Fox will play footman Andy.