The BBC press office have released details of the 9th episode of Series 6, The Night Terrors.
The Doctor receives a distress call from the scariest place in the Universe: a child's bedroom.

Every night George lies awake, terrorised by every fear you can possibly imagine – fears that live in his bedroom cupboard. His parents are getting desperate – George needs a doctor.

Fortunately for George, his desperate pleas for help break through the barriers of all time and space and the Doctor makes a house call. But allaying his fears won't be easy; because George's monsters are real. 
 The episode, written by Mark Gattis airs on 3rd September.