The BBC Media Centre have released the synopsis for Neil Gaiman's "Nightmare In Silver" which is due to air on BBC1 on Saturday 11 May 2013 at a time yet to be confirmed:
Hedgewick’s World of Wonders was once the greatest theme park in the galaxy, but it’s now the dilapidated home to a shabby showman, a chess-playing dwarf and a dysfunctional army platoon.
When the Doctor, Clara, Artie and Angie arrive, the last thing they expect is the re-emergence of one of the Doctor’s oldest foes. The Cybermen are back!
Executive produced by Steven Moffat and Caroline Skinner
Directed by Stephen Woolfenden
Written by Neil Gaiman
Produced by Denise Paul
Series produced by Marcus Wilson