As for inside, she knew the world was a much stranger place than she’d once thought, but alongside the rock of her family on which her two small feet were so securely planted she had discovered a shining ivory tower whose staircase spiraled to the stars. Mathematics. By ten she was doing the family accounts and not long afterward her pa was using her to double-check the Vinada books. But already it was clear that her abilities went far beyond mere bookkeeping. Any disappointment her ma and pa felt that she was lost to the family business they kept to themselves, and it was with their blessing and encouragement that she went off to university after a gap year which (unlike Martie who spent it jetting around Europe in the company of well-heeled boyfriends) she devoted to exploring Australia.

Now to the established certainty of her own identity and her growing confidence that anything that couldn’t be explained by mathematics probably wasn’t worth explaining was added a proud assurance that she lived in one of the most varied and fascinating countries in the world. At that point in her life she could see no reason why she should ever want to leave it.

At university she quickly established herself as one of the brightest maths students of her year. Nor was there any question of geekiness. She worked hard, but huge natural ability plus an eidetic memory meant she had plenty of time to do all the other things a student ought to do, like getting hammered, and getting a suntan, and getting laid, as well of course as getting mad. The first three she did most frequently in the company of another brilliant math student till his chosen specialist path of cryptography got him recruited by government men so anonymous even their suits had no labels.