Kit Harington and Mark Gatiss team up for BBC Christmas Ghost Story Lot No.249

In theory, it should still be familiar ground for Gatiss – he was the co-writer of the Benedict Cumberbatch-starring Sherlock, which put a modern-twist on Conan Doyle’s most famous creation – but it seems Lot No 249 may be different from both his previous ghost stories and the detective series.

Gatiss explains: “MR James is very much about a slow accumulation of dread – you often start with quite normal circumstances, usually with a middle-aged bachelor who transgresses some unwritten supernatural law or finds something he shouldn’t have and then is gradually hunted down by a vengeful spirit.

“The Doyle story is much more of a straightforward horror archetype – it’s about reviving the dead, it’s about the mummy as an instrument of revenge. Doyle is a very different writer to James – he’s one of the greatest short story writers we’ve ever produced. He writes the Victorian man and the strange threats they encounter rather brilliantly.”

And the fact that it doesn’t feature a certain sleuth also ended up being a bonus. Gatiss says: “As a fan and a scholar of Doyle sometimes you can read a story which feels almost like a Sherlock Holmes story and there are certain stylistic and linguistic elements where you can tell it’s written by Doyle. As someone who knows Sherlock Holmes stories as well as I do, when you read a story without Holmes it’s like having a missing chapter – there’s a strange pleasure to it.”

The tale is set in 1881 at Old College, Oxford, which is home to three very different academics – Abercrombie Smith (Harington), who seems to be the very model of a modern Victorian gentleman, the delicate and unworldly Monkhouse Lee (Colin Ryan), and the strange Edward Bellingham (Fox) who has been making waves with his research into Ancient Egypt.

Could his experiments even disturb a bag of bones tagged as Lot 249?

It may sound scary, but for the cast it’s been nothing but fun. Harington says: “I have loved Gatiss and his work for a long time and I adore his series of Christmas ghost stories. Freddie is a great, kind, generous and brilliant actor.

“It was rapid and fun and that was what Mark promised me. Let’s get in, shoot something fun and sit around at Christmas with mince pies and watch it. What a joy.”

In fact, it seems to have made the Game of Thrones star eager to take on more 19th-century literature. He says: “Gatiss clearly saw that I’m a closet Victorian man trapped in a millennial body. I loved these costumes, I loved the moustache…I’d definitely do something of this period again”