The Doctor stepped forward. Forward! He raised his right arm, pointing to the back of the chamber. ‘Go to your room!’ he said to the infant closest to them. ‘You’ve been a very naughty vampire!’ Voice raised. ‘I mean it! Go to your room!’

The children paused, exchanged glances and resumed their advance.

The Doctor caught David’s sideways look. ‘Well,’ said the Time Lord. ‘It’s worked before.’