'It's a killer puzzle box designed to scare me to death, and I'm trapped inside it.'
The Doctor is ultimately triumphant in breaking out of the trap (after a mere four billion years or so) but many fans are still stuck on some of the finer details of the journey, and in the latest issue of Doctor Who Magazine, Heaven Sent writer (and Doctor Who Showrunner) Steven Moffat was able to shed some light on some of the trickier unanswered questions.
Firstly - and maybe the key question that fans wanted answering - is the question of 'Room 12'. Most other areas and rooms in the castle (the gigantic puzzle box) reset themselves after a relatively short period of time so that the Doctor, trapped in a closed time-loop, finds them as if for the first time, each time. Room 12 is the final challenge for the Doctor and where he is being 'lured' towards in every cycle portrayed in the episode. Within this room is one final barrier to freedom, a 20 foot 'harder than diamond' wall which the Doctor punches his way through over the centuries getting that little bit further every time he finds the room. But why doesn't Room 12 also reset? Shouldn't he find the 20 foot barrier intact each time? Moffat explains:
It's not a room in the castle, it's the outer wall of the confession dial. The clue is that it's 20 foot of harder-than-diamond. Why bother making it so hard if a resetting stone wall would do?It makes sense that the Doctor was always destined to break out of his prison, but as the Doctor says, he does it 'the long way round'. In the final episode Hell Bent we come to understand the Doctor could have freed himself at anytime simply by providing information about 'The Hybrid'.
Next Moffat has fun explaining the question of the Doctor's clothes - after crawling out of the lake filled with skulls of his previous selves, why does he find a new set of his clothes waiting for him dried by the fire of the next room he finds? Might there have been a moment in the time loop where the Doctor completes the circle naked? Moffat laughs off the idea:
Naked Doctor Who? It’s AGAINST THE LAW, I tell you, Showrunners have been executed for less. No, of course there wasn’t – I sort of wrote that moment to force you to think that the first time round the castle (the first of many times) wasn’t the same as the version we sawMoffat says that in his own mind the Doctor originally finds there a set of ordinary clothes, not his own, and it would seem having changed into them, alters the nature of the loop:
Next time round, the Doctor finds his own clothes drying for him. The loop is complete – the end now triggers the beginning and that makes it permanentMoffat goes on to explain some of the other mysteries in the episode such as the random clues the Doctor seems to discover have actually been left there through his previous efforts in the search for Room 12 in the hope they will avoid being reset. A great example of this is the Doctor painfully drawing out the one word clue 'Bird' in dying moments, (maybe to inspire his next self in the cycle to remember the legend he later quotes whilst punching through the wall, in which a bird is a key factor). Moffat continues:
The first time round the castle, the Doctor is there for many years, because there is no clue leading him to room 12. He’s ancient by the time he understands that room 12 is important.And the answer to one last mystery, who painted the ancient portrait of Clara we see early on in the episode? Well of course it was the Doctor himself who Moffat says was being 'Soppy'. Let's not get too worried by where he finds the various paints, personally I think the stash of soup the Doctor has apparently sourced must come in a whole bunch of varieties and colours, right?.
After a few thousand years of this, he realises he’s going too slowly. He needs to get the next version of himself into room 12 faster.
The loop shrinks, the Doctor is younger as he punches the wall, and the Time Lords tremble as the storm grows closer.