Genjiro makes pottery. He doesn't forge weapons, and he refuses to waste his talent making cheap clay jars for soldiers. When he defies the Seto Clay Guild, they strip him of everything. They seize his clay, cast him out, and shut their gates behind him.

Now he lives on a cold hillside outside Kamakura with nothing but a broken potter's wheel, a spade, and one impossible dream: to recreate the legendary sea-green glaze of the Song Dynasty. But the rare volcanic stone needed for that glaze can only be found in the dangerous Hakone mountains, where smoke rises from the earth, cliffs tower overhead, and armed guards watch every pass.

Sayuri knows those mountains better than anyone. Her family protects the mountain passes, and her temple needs medicine jars strong enough to survive the harsh winter. She agrees to guide Genjiro, but the guild has no intention of letting him succeed.

As the Shogunate announces a grand pottery contest, the guild cuts off his supply of firewood and uses the law to crush any chance he has of competing. To fire his kiln hot enough to create the glaze, Genjiro must decide how much he is willing to sacrifice and whether he can stop facing the world alone before everything he has worked for is reduced to ash.