Linn has a compact, sturdy frame and a spring-loaded way of moving, as if every step might turn into a dash toward someone in trouble. She favors her left side when standing still, unconsciously angling her body between others and the nearest exit. Her thick black hair is cut in an uneven bob and pinned with bright paper stars; loose strands stick to her forehead when she runs. Her transformation outfit is a puffed white-and-coral jacket over a pleated skirt, with striped leggings and a broad sash knotted like a festival prize ribbon. The jacket is patched at the elbows and faintly smells of rain-soaked wool. At first glance she looks like a cheerful parade mascot; a minute later, most people notice her thumb repeatedly checking the little star-shaped clasp at her collar.

Linn is boisterous when a room needs courage and unexpectedly frank with people she trusts. She loves making others laugh, yet resents being treated as a symbol of unbreakable joy. In a crisis she is decisive and physical; afterward, when everyone is safe, she can become restless and self-critical. She collects tokens of gratitude because she wants proof that a frightening day ended with connection, not only loss.

Linn grew up helping her aunt run a roadside tea stall near the flood-prone district of Kettik. She learned to lift waterlogged crates before she learned to read, and to make frightened children laugh while adults argued about whose roof had failed. During the disastrous Bell-Sinking, a storm surge tore through the district. Linn's younger brother Krez was trapped in a collapsed washhouse, and Linn found that her anger could become a brilliant, absurdly frilled suit of armor that let her haul beams aside. She saved him, but could not reach everyone. Afterward she began collecting tiny gifts from people she protected: a button, a paper fish, a cracked marble. They remind her that rescue is not the same as being able to save everyone. She now travels with a small band of volunteer escorts, the Unbreakable Parade, an ironically boastful name chosen when they were children and kept because changing it feels unlucky. Her friend and fellow escort Drav wants to turn their work into a paid guard company; Linn fears that would leave the poorest people unprotected. She is also trying to persuade Krez, now a practical-minded ferry mechanic, to leave the flood district before the next storm season.