There was once a woman who lived on her own and had no children. One day, she was surprised to realise that she was pregnant.

‘This is very strange,’ she said to herself. ‘How could this have happened?’

And as she spoke these words, a spirit appeared before her.

‘Rejoice, woman!’ said the spirit. ‘You are fortunate, for you have been chosen to bear a Child who will become the progenitor of a great race. Go forth and be happy, and I shall appear to you again.’

This didn’t do much to reassure the woman, especially when she looked up ‘progenitor’ in a dictionary. ‘Goodness me,’ she said to herself. ‘My child will found a new race? What does that even mean? I never asked for this.’

The woman went about her life, feeling rather annoyed about the whole business, until eventually she gave birth. It happened quite suddenly, when she was on a walk through some trees near her home. She had been completely unprepared, but the process was surprisingly painless.

‘Well,’ she said to herself when it was done, ‘that was much easier than I was expecting.’

Then she looked down and saw the child, and she saw that it was all wrong. The head was the wrong shape. The body wasn’t that of a normal child. And it was all covered in dark fur.

‘What is this?’ she cried. ‘This is not a human child. This is some sort of awful creature. I have given ...