Tweeting on the Orient Express - Agatha Christie goes social

With her page-turning detective mysteries and murder whodunnits, Agatha Christie's novels have won over generations of fans since they were first published 95 years ago.

Now, in a world of smartphones and tablets, her work is being targeted at digital audiences with an app telling one of her tales through a social media feed of messages, photos and videos.

Based on Christie's set of short stories "The Mysterious Mr Quin", the pilot "Mr Quin" launched on Thursday is being billed as the first digital drama of its kind.

Agatha Christie Productions has teamed up with entertainment mobile platform TELL to bring the eponymous Quin and socialite Satterthwaite into a contemporary setting.

The story, in which characters talk to each other via Twitter-like text, images and videos, begins at a country manor party where hostess Lady Laura plans to unveil her new online venture.

But the tone soon darkens when a mysterious Mr Quin takes over Satterthwaite's live blogging of the event, turning the conversation to the suicide, five years ago, of the guests' mutual friend.

"All of the characters tell their stories on social media so, you voyeuristically look in at their worlds as the story comes out," TELL interactive director and producer Kevin Moss said. "We kind of call it an entertainment stream and you literally use your thumb to scroll up and down the timeline."

Viewing is on demand or via an immersive scheduled show, in which audiences receive messages and can participate by posting comments.

To give a sense of real footage, the production, starring "Game of Thrones" actor Gethin Anthony as Satterthwaite and Rebecca Scroggs as Lady Laura, was shot on GoPros and iPhones.

"(In) any whodunnit ... murder mystery, it's always interesting, you have your opinions," Scroggs said. "And this way you can actively share that."

Christie, who died in 1976, wrote dozens of stories, which followed much-loved characters such as moustached detective Hercule Poirot and elderly Miss Marple.

"Christie ... used to keep all of her fan letters and she replied to every single one," Julia Wilde, director of business development at Agatha Christie Limited, said.

"So we truly believe she would have absolutely loved this type environment where you can have that direct contact with your fans on a daily basis, right down to the minute detail."