On one of the few occasions that I lulled Zac into talking about Jane, he said it would have been pointless for him to search for her. She loved travelling, he said. China was among the many places she visited in the years before she left him. He sometimes went with her, if he could get away from work. He certainly travelled a lot during the time we lived together. Doing this reduced his ability to watch me, so the incentive must have been high. Fleeing via China would be perfect for somebody who wanted a route that flew over countries without extradition to the US or the UK. George said that after he escaped the US, Frederick met Zac and Jane. China seems to me to be a likely place for that.

I can understand why Jane would want to help Frederick. No real family apart from Zac. As an only child myself, with no living parent, I know how eagerly I would have seized on the sudden and unexpected gift of a brother, and how seriously I would have taken my loyalty to him. Maxine said when she found me on the cliffs all that time ago that Jane hadn’t known about Frederick’s existence until after their father died. They must have started to get close soon after that, but before Frederick released those secrets and ran. And Zac must have got close to Frederick along with her.

I try to imagine more about how it all looked to the intelligence agencies. Presumably they reasoned that Jane couldn’t have stayed under the radar as perfectly as she did without exceptional help. And Frederick had the ability to provide that help. He makes Snowden look like an amateur. That was what George had said. They wanted to find Jane – and put pressure on Zac – because they thought that was their best route to Frederick.

But why did things become so intolerable for Jane that she had to flee, while Zac was able to stay and live a relatively normal life after she left? Perhaps they had more evidence against Jane than they did Zac? Then again, not everything is about international surveillance. I know better than anyone what living with Zac entailed. That, on its own, would be enough to explain why she ran.