September 2003. A late-night drive on a closed backroad in Harlow County, Tennessee. Luna's car dies at the base of Sawmill Creek Bridge — a single-lane iron span the county decommissioned after three disappearances in the late '90s. She walks the bridge alone, flashlight flickering, and finds a door set into the concrete foundation beneath the deck: a six-panel wooden door, painted the same dull green as the rusted railing, fitted with a brass knob that turns freely. What she finds behind it is not a storage vault or a maintenance crawlspace. It is a room with a chair, a lamp, a stack of letters, and a smell like wet earth. The letters are addressed to her by name — in handwriting she recognizes but cannot place. A quiet, claustrophobic episode about roads that lead where they shouldn't, and doors that open for the person they expect.