In The Chrysalids, chapter 12, Michael informs David, Petra, and Rosalind that all three of them have officially been classified as deviants. This means that they are considered less than human, and anyone may hunt them down to kill them. Michael tells them that there is an even greater reward for anyone who can capture them and bring them back alive.
David reasons that they will have to flee into the Fringes now that hunters are after them. Michael tells David that he will try to think of some way to fake their deaths to keep hunters off their scent. At this time, David discovers that Petra isn't exactly enthused about going into the Fringes. Michael tries to connect to her through thought-forms in order to reassure her that the Fringes is not the frightening place many people make it out to be. However, Petra soon tells Michael that his thought-pictures are mixed up with someone else's.
Petra is encouraged to let the other girl know what their location is. However, the other girl has a hard time picturing their location based on Petra's descriptions. Eventually, Petra tells them that she sees lots of houses where the other girl is and that she also sees flying things in the air. This reminds David of his childhood dream where there are "shiny, fish-shaped things" in the sky. Petra tells him that this is exactly what she sees at the other girl's location.
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