Another gap in my knowledge was how Sentinel, created as a deterrent to violence, had come to destroy the Beforetime. Perhaps Cassy and Hannah had never known exactly how the Great White came about. I did know from my past-dreams of Cassy that the Sentinel Project had been very near completion at the time of the Great White. It had always been my suspicion that when Sentinel had been tested, something had gone wrong, causing it to unleash the Balance of Terror arsenal. No dream supported this theory but I could not believe that even the most power-hungry and heedless Beforetimers would have deliberately brought about the end of their world. As to why Sentinel would target so many different locations yet stop short of complete destruction, the only thing I could think of was that someone had managed to disrupt the operation of the Balance of Terror weapons before they could destroy everything. Yet supposedly they and Sentinel had been designed to be unassailable, beyond any human interference.

My dreams of Cassy showed that initially Hannah had believed the disaster she had seen could be averted. She and her friends had worked to this end, but at some point she had understood that the holocaust was inevitable. I did not know how long after she had acquired this dark knowledge that she had foreseen the coming of the Seeker. Perhaps it was only when she dreamed about me that she understood she could not stop the Great White from happening, that I alone would have the potential to end the threat of a second holocaust.

Nor did I know if she or Cassy had ever foreseen the coming of the Destroyer, who would be born in the same time as the Seeker, and have the potential to use Sentinel and bring the world to a final doom. I suspected they must have known or seen something of him, for it was the only explanation for the cryptic nature of the directions Cassy had left me. They had been so obscurely phrased and so difficult to interpret that I was sure Cassy had been striving to make sure no one but I would be able to make head or tail of them.

That was what I thought, but I did not know.