In Salt-Howl, the dead are kept below by a bell and a flame. Twice a day the Whelm Bell rings from the Tooth, and twice a day the blue flame in the Lantern Chapel drinks whatever offering the town can spare — a name, a face, a remembered lullaby — to hold the tide and the drowned it carries.

Nessa Vale is the ringer's foundling, a girl who cannot forget. While the flame eats the memories of everyone else in Salt-Howl, it cannot touch hers. As old Esh Kettle burns himself hollow to protect her, Nessa begins to recover the memories the flame has already consumed — and the drowned begin to whisper her name.

The truth beneath the bay is older than the chapel. The drowned are not the town's enemies. They are its dead, burned out of remembrance by a liturgy that was never meant to feed on forgetting. And the Lady of the Tide, queen of the sunken town of Old Alderholm, is calling her people home.

To save Salt-Howl, Nessa must do what no ringer has done in three centuries: ring the bell at the turning of the tide, walk down the tide-stairs, and give the drowned back what was stolen from them — their memory. But first she has to choose what she is willing to burn.