On The Vigil, you are born owing. It runs the worst loop on the network — a frontier circuit through mountain and raider country — and it survives like a fortress: everyone drilled to a function, the carriages armoured, the enemy outside the glue that holds it together. Underneath the watch-rosters runs a ledger. Every passenger owes for their berth, their ration, their protection, and the debt is collected without apology. Cass Renick has collected it for twenty-five years, and made her peace with hardness as the price of survival — until a man comes through the Passage remembering the one thing no arrival should.