The BBC have released the synopsis for the 9th story in in Series 8 Flatline. It will air October 19th at 8:30PM on BBC One.
Separated from the Doctor, Clara discovers a new menace from another dimension.
But how do you hide when even the walls are no protection? With people to save and the Doctor trapped, Clara comes up against an enemy that exists beyond human perception.
Written by Jamie Mathieson
Directed by Douglas MacKinnon
Guest star - Christopher Fairbank