The final TARDIS scene. Whether or not the Master would start the TARDIS before the Doctor is inside, as if to say ‘Hurry up Doctor, get into the TARDIS, I’m ready to go’ – We had a big debate about this and whether or not the TARDIS had ever been started up without the Doctor at the console.

In our case it is and they have to rush to get inside and the doors closed exactly behind them but these were the kind of questions, it stopped our rehearsal process to a standstill as we discussed whether or not this could happen and then we went back and listened to every TARDIS dematerialisation process ever.