From the Primer, a Visit to Castle Turing Summary

Nell surveys the territory entered by her fictional alter ego and she realizes that she will have to visit seven castles before she can recover the stolen keys. By now, Constable Moore disappears frequently into Chinese territory for weeks at a time. When he gets back, he drinks heavily and plays his bagpipe into the night.

The Illustrated Primer continues its story as Princess Nell knocks on the door of the first castle. She is immediately imprisoned by mechanical guards in what is revealed as Castle Turing. The guards are robots who seem to respond to orders given through chains of binary commands. She manages to communicate with someone who calls himself Duke of Turing, using the chains she finds everywhere. By communicating a poem to the Duke, she...