Appears In: Riven
I write quickly from my prison...
Nelah will return your book which the Moiety intercepted upon your arrival. After questioning her, I've concluded that it was written by Atrus for a very specific purpose.
Gehn will desire to use it... although he may have suspicions.
If you can find my prison, you will still need the combination to release me; Gehn keeps it in his office. Then, I assume, we're to signal Atrus... I think I know how it might be done. But don't signal him before I am released.