A hundred years ago, in a wreck nobody in Kivela remembers anymore, Lake Superior gave a Korhonen woman her life back out of the water. It was not a gift. The lake keeps what it is given, and a life handed back is a life still owed. Every keeper since has paid the interest. Nell Korhonen has spent two hard seasons finding that out, and she is on the ledger herself now, carrying the lake's own time inside her, slipping toward it whenever she is tired or cold or too long alone at the top of the tower. There is one way out, and her mother's notebook finally gives it to her, because she is finally strong enough to be told. The loan can be cleared. Once, and only once, by a reader who can go down into the greenstone and read the founding bargain entire.

Nobody has ever done it. The women who tried are the reason this family stopped speaking of it out loud. If she can hold the whole of it, the lake stops collecting from the people she loves. If she cannot, the light keeps her, the way it has kept every keeper who reached too far. She has one season either way.