The cast of Casualty are set to film a special one-off Halloween ‘webisode’ – the first web-only episode ever to be screened by a BBC continuing drama.

The eight-minute special will follow homeless man Alistair (Joe McFadden) and paramedic Polly’s (Sophia di Martino) story from the end of the televised episode on Saturday, October 31 until the start of the next show.

The webisode will see Alistair’s decent into madness and the gritty world of life on the streets as Polly calls the police on him.

Executive producer Belinda Campbell said: “We are always looking at new ways to add value for our loyal fans and this innovative mini-episode will open a window on a hitherto unseen world and give viewers access to a character they wouldn’t have in a normal episode.

“David, Joe and Sophia have worked really hard to make this a really special viewing opportunity for die-hard Casualty lovers”.

Joe McFadden said: “It was really interesting to shoot in a very different way and great fun to explore my character in a bit more depth and show a gritty side of Casualty that viewers don’t normally get to see.”

The ‘Casualty – The Parting of Ways’ webisode can be seen on the show’s website, via the red button and as a downloadable mobisode on October 31 after the night’s televised episode is broadcast.