This episode goes behind the scenes of A Good Man Goes to War

Confidential goes behind the scenes for the epic series finale set on the asteroid, Demons Run.

We discover how the Doctor Who team create the newest baddies, turn a small platoon of clerics into an army and transform an alley in Cardiff into Jack the Ripper's London.

Features a day in the life of a Doctor Who enemy and in-depth interviews with Karen Gillan, Arthur Darvill, Alex Kingston, Frances Barber and lead writer Steven Moffat.