Chapters 17-20 Summary

Chapter 17. Demonreach says that while Dresden is the warden of the magical prison, he is the guard, the order. The evil creatures are held in the prison so they can do the least harm, and they cannot get loose without outside help, unless Dresden authorizes it. Dresden is concerned about being given such power. He begins to develop a headache, and Demonreach "warns it away," revealing that it is caused by a parasite that will endanger him in the future, eventually bursting from his skull. Demonreach tells him Molly will help him get it out in the future. Dresden puts this concern aside, and asks Demonreach to explain the problem with the prison. Bob translates Demonreach's explanation into language Dresden can understand, showing him that Merlin built the island in various time dimensions, and it is reinforced by many complicated enchantments...