The Somnatorium is a room in Exile where the irredeemable cases are kept. It is located not far from where the participants of the raid on Exile entered in Book 4: Neverseen. The prisoners in there are constantly sedated and are in a permanent sleep. When Sophie first heard of this, she connected their state to death, though Blur says they are very much alive, which keeps guilt away from the Councillors' minds. It connects to the main corridor of Exile.