Jeju Island, Summer 1943

Hana is sixteen and knows nothing but a life lived under occupation. Japan annexed Korea in 1910, and Hana speaks fluent Japanese, is educated in Japanese history and culture, and is prohibited from speaking, reading, or writing in her native Korean. She is a second-class citizen with second-class rights in her own country, but that does not diminish her Korean pride. Hana and her mother are haenyeo, women of the sea, and they work for themselves. They live in a tiny village on Jeju Island’s southern coast and dive in a cove hidden from the main road that leads into town. Hana’s father is a fisherman. He navigates the South Sea with the other village men, evading imperial fishing boats that loot Korea’s coastal waters for produce to repatriate back to Japan. Hana and her mother only interact with Japanese soldiers when they go to market to sell their day’s catch. It creates a sense of freedom not many on the other side of the island, or even on mainland Korea, a hundred miles to the north, enjoy. The occupation is a taboo topic, especially at market; only the brave dare to broach it, and even then only in whispers and behind cupped hands. The villagers are tired of the heavy taxes, the forced donations to the war effort, and the taking of men to fight on the front lines and children to work in factories in Japan.

On Hana’s island, diving is women’s work. Their bodies suit the cold depths of the ocean better than men’s. They can hold their breath longer, swim deeper, and keep their body temperature warmer, so for centuries, Jeju women have enjoyed a rare independence. Hana followed her mother into the sea at an early age. Learning to swim began the moment she could lift her head on her own, though she was nearly eleven the first time her mother took her into the deeper waters and showed her how to cut an abalone from a rock on the seafloor. In her excitement, Hana lost her breath sooner than expected and had to race upward for air. Her lungs burned. When she finally broke the surface, she breathed in more water than oxygen. Sputtering with her chin barely above the waves, she was disoriented and began to panic. A sudden swell rolled over her, submerging her in an instant. She swallowed more water as her head dipped beneath the surface.

With one hand, her mother lifted Hana’s face above the water. Hana gulped in air between racking coughs. Her nose and throat burned. Her mother’s hand, secured at the nape of her neck, reassured her until she recovered.

“Always look to the shore when you rise, or you can lose your way,” her mother said, and turned Hana to face the land. There on the sand, her younger sister sat protecting the buckets containing the day’s catch. “Look for your sister after each dive. Never forget. If you see her, you are safe.”

When Hana’s breaths had returned to normal, her mother released her and commenced diving with a slow forward somersault down into the ocean’s depths. Hana watched her sister a few moments longer, taking in the serene sight of her resting on the beach, waiting for her family to return from the sea. Fully recovered, Hana swam to the buoy and added her abalone to her mother’s catch, which was stowed safely in a net. Then she performed her own somersault, down into the ocean’s thrumming interior, in search of another sea creature to add to their harvest.

Her sister was too young to dive with them when they were that far from the shore. Sometimes, when Hana surfaced, she would look first to the shore to find her sister chasing after seagulls,...