The Halloran rooming house is still smoking when Investigator Edda Voss arrives at dawn. Eight survivors sit on the curb under scratchy blankets, faces black with soot. The landlord's ledger lists nine tenants, nine rent stubs, nine keys collected every New Year. Edda counts the survivors twice. Eight. So where is the ninth tenant, and which clue does she chase first?

Edda steps over the warm threshold and into the burned house. The fire crew waves her back, but she pushes upstairs to room 9. The door is locked. She tries each of the eight keys the landlord saved. None of them fit. The ninth key is gone.