Doctor Who: 13 Cool Details Revealed In Steven Moffat's Time Of Angels Commentary
3. The Crew Had Arguments About Using The Doctor's Heroic Musical Theme
The big twist in the episode is that every single statue in the maze is actually a Weeping Angel, meaning that the Doctor has led everyone into complete and utter danger.
During the scene where this twist is unveiled, a darker variant of Murray Gold's I Am The Doctor begins to play. The normal version of this track is generally associated with the Doctor doing heroic, good things - hence why it was made to sound more sinister for this scene, in which he's made a fatal mistake.
The use of this darker variant stemmed from an argument between Moffat and Piers Wenger. Wenger felt that the normal hero theme should be played, whereas Moffat felt that the scene demanded a more sombre tone.
So, in the end, a compromise was made: the hero theme was used, but it was made to sound more edgy and dark.