The Blair Letter House's precept: 'Do not receive Nether Letters at midnight. Nether Letters must not be opened, stored, or delivered.' Breaking this rule means haunting by spirits. When grandpa Zane Blair needs Mr. Dexter Shaw's herb for grave illness, Claire Blair is urged by Quinn Sutton and Mr. Shaw to break the rule, accepting a Nether Letter at midnight. Haunted by Julia Linden, she must help find her murderer and uncover the truth.
